Inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-lasting drip and fog-eliminating greenhouse film and its preparation method

Abstract

The present invention belongs to the technical field of agricultural film preparation, and specifically relates to an internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-acting anti-drip and anti-fog greenhouse film and its preparation method. The greenhouse film is composed of an outer layer 1 - dust-proof and aging-resistant layer, an outer layer 2 - light conversion and aging-resistant layer, an outer layer 3 - barrier heat-insulating, acid-resistant and aging-resistant layer, a middle layer - high heat-insulating, acid-resistant anti-drip agent reserve layer, an inner layer 3 - high heat-insulating, acid-resistant anti-drip agent reserve layer, an inner layer 2 - high heat-insulating, acid-resistant anti-drip and anti-fog agent slow-release layer, and an inner layer 1 - acid-resistant anti-drip and anti-fog agent release layer. The greenhouse film of the present invention has a width of more than 8 m and a thickness of 0.08 mm - 0.15 mm; the light transmittance is more than 90%, and the haze is less than 16%; the infrared transmittance is less than 20%; when the film is covered for 600 days, the ratio of the light intensity inside and outside the greenhouse is still greater than 88%; the dust-proof function makes the annual attenuation rate of the light transmittance less than 1.1%; the anti-drip and anti-fog function has a long-lasting period of 24 months, which is synchronized with the life of the film.

Description

Technical Field

[0001] The present invention belongs to the technical field of agricultural film preparation, and particularly relates to an internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-lasting dripping and fog-eliminating greenhouse film and a preparation method thereof. Background Art

[0002] Agriculture is the foundation of the national economy, and greenhouse film is an important material for agricultural facility horticulture. At present, the annual output and consumption of polyolefin agricultural greenhouse films in China are about 1.05 million tons, ranking among the top in the world. Moreover, the market development speed of multi-functional high-end agricultural greenhouse films is growing at a double-digit rate every year. There are mainly two types of compositions of functional greenhouse films for greenhouse covering materials existing in the market.

[0003] One is the coated film: It can achieve the functions of dripping and fog elimination in complete synchronization with the service life of the film. However, due to the long process, high equipment cost, relatively complex process, and high requirements for the performance and quality of the coating liquid, it is more suitable for producing high-grade films with a service life of more than 3 years. The other is the internally added dripping and fog-eliminating greenhouse film: It is produced by using the traditional masterbatch processing technology. The internally added dust-proof masterbatch, light conversion masterbatch and various surface-active dripping and fog-eliminating masterbatches are added into the film to prepare the light conversion, dust-proof, dripping and fog-eliminating greenhouse film. The function of dripping and fog elimination is achieved through the gradual precipitation of the surfactant in the film. The internally added dripping and fog-eliminating greenhouse film is easy to operate, has low processing energy consumption and good quality stability. However, the lasting period of dripping and fog elimination is only 4 - 7 months, which cannot meet the needs of the development of modern high-efficiency agricultural facilities. If the effective period of dripping and fog elimination can be increased to more than 24 months, and at the same time, the functions of light conversion, dust-proof, high heat-insulating and pesticide-resistant are added, the market development potential is huge. However, the action mechanism of the internally added dripping and fog-eliminating greenhouse film is to realize the migration and precipitation through the concentration gradient of the dripping agent in the film, generate the dripping effect and flow away along the film surface, which is completely different from the coated film that adsorbs the water vapor in the greenhouse to fill the porous gaps of the inorganic glue solution. When the concentration gradient of the dripping agent tends to zero, the dripping performance completely fails. To achieve a stable long-lasting dripping and fog-eliminating function, the problems of sufficient reserve and uniform precipitation of the dripping agent and the fog-eliminating agent must be solved. At present, the comprehensive functions of long-lasting dripping, dust-proof, light conversion, high heat-insulating and pesticide-resistant in the internally added greenhouse film are still relatively backward. Restricted by the performance of processing equipment and the relative synergistic effect or negative synergistic effect of functional additives, the functions of dust-proof, light conversion, high heat-insulating, pesticide-resistant and dripping and fog elimination on the market cannot coexist synergistically, and only two or three functions are available.

[0004] Due to the relatively high multiple cropping index in plastic greenhouse, the usage of chemical fertilizers and pesticides has increased too rapidly. During the use of pesticides, the sulfur and chlorine components in pesticides will react with water molecules in the greenhouse to form sulfurous acid (H2SO3) and hydrochloric acid (HCl), which will undergo acid-base neutralization reactions with hindered amine light stabilizers 944 (N-H type, relatively alkaline) and 783 with stronger alkalinity in the greenhouse film. As a result, the activity of the hindered amine light stabilizer in the agricultural film is passivated, making it unable to capture the oxidation free radicals that promote the chain breakage of polymers, and accelerating the disintegration and damage of the greenhouse film. Pesticides containing sulfur and chlorine have a greater impact on the weather resistance life of the greenhouse film. To solve the problems existing in the prior art, it is urgent to develop a multi-functional greenhouse film with comprehensive functions and more reliable quality. The invention of an internally added high-end comprehensive functional greenhouse film to meet market demand, achieve long-term dripping and fog elimination for more than 24 months, and at the same time achieve self-cleaning, dust-proof, light conversion, high heat preservation, and pesticide resistance functions is exactly the research topic of this invention. Summary of the Invention

[0005] The object of the present invention is to provide an internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat preservation, pesticide-resistant, long-term dripping and fog elimination greenhouse film. This greenhouse film has comprehensive functions of dust-proof, light adjustment and conversion, high heat preservation, pesticide resistance, and long-term dripping and fog elimination period; the present invention also provides its preparation method.

[0006] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, highly heat-insulating, pesticide-resistant, long-lasting dripping and fog-eliminating greenhouse film of the present invention is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1; wherein the outer layer 1 is a dust-proof and aging-resistant layer. By mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 80%-88%, acid-resistant and aging-resistant masterbatch 5%-10%, and dust-proof masterbatch 7%-10%; the outer layer 2 is a light conversion and aging-resistant layer. By mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 20%-30%, linear low-density polyethylene (LLDPE) 15%-25%, metallocene linear low-density polyethylene (mLLDPE) 35%-45%, light conversion masterbatch 8%-12%, and acid-resistant and aging-resistant masterbatch 5%-10%; the outer layer 3 is a barrier, heat-insulating, acid-resistant and aging-resistant layer. By mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 15%-25%, metallocene linear low-density polyethylene (mLLDPE) 55%-65%, acid-resistant and aging-resistant masterbatch 5%-10%, and heat-insulating masterbatch 10%-15%; the middle layer is a highly heat-insulating, acid-resistant, and dripping agent reserve layer. By mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 57%-68%, acid-resistant and aging-resistant masterbatch 5%-10%, dripping masterbatch 15%-25%, and heat-insulating masterbatch 8%-12%; the inner layer 3 is a highly heat-insulating, acid-resistant, and dripping agent reserve layer. By mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 60%-72%, acid-resistant and aging-resistant masterbatch 5%-10%, dripping masterbatch 15%-18%, and heat-insulating masterbatch 8%-12%; the inner layer 2 is a highly heat-insulating, acid-resistant, dripping and fog-eliminating agent slow-release layer. By mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 67%-72%, acid-resistant and aging-resistant masterbatch 5%-10%, dripping masterbatch 12%-15%, fog-eliminating masterbatch 1%-3%, and heat-insulating masterbatch 5%-8%; the inner layer 1 is an acid-resistant, dripping and fog-eliminating agent release layer. By mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 77%-84%, acid-resistant and aging-resistant masterbatch 5%-10%, dripping masterbatch 8%-12%, and fog-eliminating masterbatch 1%-3%.

[0007] Among them:

[0008] The specific parameters of the raw materials used in the outer layer 3, outer layer 2, and outer layer 1 are as follows:

[0009] The density of low-density polyethylene (LDPE) is 0.920 - 0.923 g / cm 3 , and the melt index (MI) is 0.2 - 0.75 g / 10 min; preferably, the low-density polyethylene (LDPE) is any one or two of 2420D or 2426F produced by Daqing Petrochemical.

[0010] The density of linear low-density polyethylene (LLDPE) is 0.918-0.922 g / cm 3 , the melt index (MI) is 0.8-1.0g / 10min; preferably, the linear low density polyethylene (LLDPE) is any one of 1001AV produced by ExxonMobil, 9085 produced by Tianjin Union Carbon or 0209AA produced by Shanghai Secco.

[0011] The density of metallocene linear low-density polyethylene (m-LLDPE) is 0.918-0.927 g / cm 3 , the melt index (MI) is 0.5-1.0g / 10min; preferably, the metallocene linear low-density polyethylene is any one or more of 2010MA, 1018MA, 2005MC or 2705MC grades produced by ExxonMobil.

[0012] The dust-proof masterbatch is brand EFT997 produced by Tianjin Riken Co., Ltd.; or brand BE-10F maleic anhydride grafted dust-proof masterbatch, produced by Jilin Baien Plastic Technology Co., Ltd.

[0013] The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in each layer are as follows:

[0014] Calculated by mass percentage, the acid-resistant and aging-resistant masterbatch is composed of the following raw materials: 45%-53% of low-density polyethylene (LDPE), 30%-40% of linear low-density polyethylene (LLDPE), 12%-15% of light stabilizer, and 2%-3% of antioxidant.

[0015] Wherein: the melt index (MI) of the low-density polyethylene (LDPE) in the acid-resistant and aging-resistant masterbatch is 2.0g / 10min, preferably any one of the 2102TN00 produced by Qilu Petrochemical or the 2426H produced by Daqing Petrochemical; the melt index (MI) of the linear low-density polyethylene (LLDPE) is 2.0g / 10min, and the appearance is powder. Preferably, the linear low-density polyethylene (LLDPE) is 7042 produced by Qilu Petrochemical or 1820 produced by Tianlian Chemical. The light stabilizer is any one of the following: the light stabilizer is a hindered amine acid-resistant light stabilizer, and the hindered amine acid-resistant light stabilizer is at least one of 2011AR, XT-100 or T-69. The manufacturers of 2011AR and XT-100 are BASF, and the manufacturer of T-69 is Beijing Tiangang Company. The antioxidant is a composite type of hindered phenols and phosphites, and preferably, the antioxidant is any one of B215 or B225. The manufacturers of B215 or B225 are both Tianjin Lianlong Company.

[0016] The preparation method of the acid-resistant and aging-resistant masterbatch is as follows: Add low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), light stabilizer and antioxidant into a kneader according to a proportion for kneading and plasticizing, then feed it into a single-screw extruder granulator through a two-roll mill, and obtain the acid-resistant and aging-resistant masterbatch through hot cutting granulation and air-cooling drying.

[0017] Among them: The temperature of the kneader is 125-140 °C, the plasticizing time is 15-20 minutes, and the temperature of the single-screw extruder granulator is 140-170 °C.

[0018] The heat-insulating masterbatch is composed of the following raw materials in terms of mass percentage: 18%-25% of low-density polyethylene (LDPE), 15%-20% of linear low-density polyethylene (LLDPE), 55%-65% of hydrotalcite heat-insulating agent, 1.0%-2.0% of coupling agent, 0.5%-1.5% of lubricant, and 0.5%-1.5% of dispersant.

[0019] Among them: The melt index (MI) of the low-density polyethylene (LDPE) in the heat-insulating masterbatch is 2.0 g / 10 min, and any one of 2102TN00 produced by Qilu Petrochemical or 2426H produced by Daqing Petrochemical is preferred; the melt index (MI) of the linear low-density polyethylene (LLDPE) is 2.0 g / 10 min, and the appearance is powder. Preferably, the linear low-density polyethylene (LLDPE) is any one of 7042 produced by Qilu Petrochemical or 1820 produced by Tianlian Chemical; the hydrotalcite heat-insulating agent, and the preferred grade is HTP, manufactured by Sakai Chemical Co., Ltd. in Japan, or any one of the grade HT3 produced by Dandong Xiehe Co., Ltd.; the coupling agent is any one of titanate or aluminate, both produced by Qingdao Jisi Chemical Co., Ltd.; the lubricant is two or any one of zinc stearate or calcium stearate produced by Hebei Zhongshang Chemical Co., Ltd.; the dispersant is polyethylene wax.

[0020] The preparation method of the heat-insulating masterbatch is as follows: Add low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), hydrotalcite heat-insulating agent, coupling agent, lubricant and dispersant into a kneader according to a proportion for kneading and plasticizing, then feed it into a single-screw extruder granulator through a two-roll mill, and obtain the heat-insulating masterbatch through hot cutting granulation and air-cooling drying.

[0021] Among them: The temperature of the kneader is 125-140 °C, the plasticizing time is 15-20 minutes, and the temperature of the single-screw extruder granulator is 140-170 °C.

[0022] In terms of mass percentage, the light conversion masterbatch is composed of the following raw materials: 36.6%-49.8% of low-density polyethylene (LDPE), 38%-45% of linear low-density polyethylene (LLDPE), 12%-18% of light conversion agent, and 0.2%-0.4% of antioxidant.

[0023] The low-density polyethylene (LDPE) in the light-converting masterbatch has a melt index (MI) of 2.0 g / 10 min, preferably any one of the grades 2102TN00 produced by Qilu Petrochemical or 2426H produced by Daqing Petrochemical; the linear low-density polyethylene (LLDPE) has a melt index (MI) of 2.0 g / 10 min, and the appearance is powder, preferably, the linear low-density polyethylene (LLDPE) is 7042 produced by Qilu Petrochemical or 1820 produced by Tianlian Chemical. any one of; the light conversion agent is preferably an inorganic rare earth light conversion agent, and the inorganic rare earth light conversion agent is any one or more of green to red GTR-650Ⅱ, green to red GTR-650Ⅲ, purple to blue VTB-440 or purple to red VTR660, all of which are manufactured by Hunan Xiweier Technology Co., Ltd.; the antioxidant is a composite of hindered phenols and phosphites, and preferably, the antioxidant is any one of B215 or B225; the manufacturers of B215 or B225 are Tianjin Lianlong Company.

[0024] The principle of selecting the light converter is that the excitation spectrum of the light converter matches the sunlight spectrum on the ground, and the emission spectrum matches the absorption spectrum of chlorophyll. According to the light quality requirements of crops, chlorophyll a mainly absorbs blue-violet light at 418nm and red light at 660nm; chlorophyll b mainly absorbs blue light at 454nm and red light at 643nm; β-carotene mainly absorbs blue-violet light at 400nm-500nm. Select one or more photoconversion agents to convert the ultraviolet light region of 290nm-390nm and green light region of 500nm-580nm, which are difficult for crops to absorb, into the best growth effect spectrum with high crop absorption rate, the blue-violet light region of 400nm-500nm, and the main peak of the emission spectrum of 440nm±30nm; the red light region of 600nm-700nm, and the main peak of the emission spectrum of 650nm±30nm, so that the converted blue-violet light and red light can be radiated into the greenhouse as much as possible, to adjust and improve the lighting environment in the greenhouse, improve the photosynthetic efficiency of crops, and achieve the effect of improving quality and increasing yield.

[0025] The preparation method of the light conversion masterbatch is as follows: low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), a light conversion agent and an antioxidant are added into an internal mixer in proportion for kneading and plasticization, and then fed into a single-screw extruder granulator through an open mixer, and then hot pelletized and air-cooled and dried to prepare the light conversion masterbatch.

[0026] Wherein: the temperature of the internal mixer is 125-140°C, the plasticizing time is 15-20 minutes, and the temperature of the single-screw extruder granulator is 140-170°C.

[0027] The melt index (MI) of the ethylene-vinyl acetate copolymer resin (EVA) in the middle layer, inner layer 3, inner layer 2, and inner layer 1 raw materials is 0.25 - 1.0 g / 10 min. Among them, the VA content of the ethylene-vinyl acetate copolymer resin (EVA) in the middle layer is 19%, the VA content of the ethylene-vinyl acetate copolymer resin (EVA) in inner layer 3 is 14%, the VA content of the ethylene-vinyl acetate copolymer resin (EVA) in inner layer 2 is 12%, and the VA content of the ethylene-vinyl acetate copolymer resin (EVA) in outer layer 1 is 7.5%.

[0028] Preferably, the grade of the ethylene-vinyl acetate copolymer resin (EVA) is any one or more of FL00012, FL00014, 00111, 00119 produced by ExxonMobil Corporation, and grades 2050, 2040, 2030 produced by Hanwha Corporation.

[0029] By mass percentage, the drip-proof masterbatch in the middle layer, inner layer 3, inner layer 2, and inner layer 1 raw materials is composed of the following raw materials: 37% - 42% ethylene-vinyl acetate (EVA) resin, 30.6% - 36.4% linear low-density polyethylene (LLDPE), 18% - 22% drip-proof agent, 0.4% - 0.6% antioxidant, and 5% - 8% ultrafine silica.

[0030] Among them: the melt index (MI) of the ethylene-vinyl acetate (EVA) resin in the drip-proof masterbatch is 2.0 g / 10 min, preferably grade 14-2 with a VA content of 14% produced by Beijing Yanshan Organic Chemical Industry; the melt index (MI) of the linear low-density polyethylene (LLDPE) is 2.0 g / 10 min, and the appearance is powder. Preferably, the linear low-density polyethylene (LLDPE) is any one of grade 7042 produced by Qilu Petrochemical or grade 1820 produced by Tianlian Chemical; the drip-proof agent is any one of KF650 or LD777. KF650 is produced by Tianjin Riken Chemical Co., Ltd.; LD777 is produced by Qingdao Siwei Chemical Industry. The antioxidant is any one of B215 or B225; both B215 and B225 are produced by Tianjin Li'anlong Co., Ltd.; the ultrafine silica is any one of grades J430 or J430B produced by Foshan Jinchun.

[0031] The preparation method of the drip-proof masterbatch is as follows: Add the ethylene-vinyl acetate (EVA) resin, linear low-density polyethylene (LLDPE), drip-proof agent, antioxidant, and ultrafine silica into a high-speed mixer according to the proportion for kneading, and then feed the kneaded material into a twin-screw extrusion granulator. After strand drawing, water cooling, pelletizing, drying, and cooling, the drip-proof masterbatch is obtained.

[0032] Wherein: the temperature of the high-speed mixer is 75-85°C, the kneading time is 12-15 minutes, and the temperature of the twin-screw extruder granulator is 150-175°C.

[0033] In terms of mass percentage, the defogging masterbatch in the raw materials of the inner 2 layers and the inner 1 layer is composed of the following raw materials: 45%-52% ethylene-vinyl acetate (EVA) resin, 35.9%-43.7% linear low-density polyethylene (LLDPE), 8%-12% defogging agent, and 0.1%-0.3% antioxidant.

[0034] Wherein: the melt index (MI) of the ethylene-vinyl acetate (EVA) resin in the defogging masterbatch is 2.0 g / 10 min, preferably 14-2 with a VA content of 14% produced by Beijing Yanshan Organic Chemical; the melt index (MI) of the linear low-density polyethylene (LLDPE) is 2.0 g / 10 min, and the appearance is powder, and the preferred linear low-density polyethylene (LLDPE) is any one of the 7042 produced by Qilu Petrochemical or the 1820 produced by Tianlian Chemical; the defogging agent is any one of KF38 or TS403 fluorosurfactants, KF38 is produced by Tianjin Riken Kaisha, and TS403 is produced by Dalian Jinlong Chemical; the antioxidant is any one of B215 or B225; the manufacturers of B215 or B225 are both Tianjin Lianlong Company.

[0035] The preparation method of the defogging masterbatch is as follows: ethylene vinyl acetate (EVA) resin, linear low-density polyethylene (LLDPE), defogging agent and antioxidant are added into a high-speed mixer according to proportion and kneaded, and then the kneaded material is fed into a twin-screw extruder granulator, and then subjected to strip drawing, water cooling, pelletizing, and entering a drying device, and then cooled to obtain the defogging masterbatch.

[0036] Wherein: the temperature of the high-speed mixer is 75-85°C, the kneading time is 12-15 minutes, and the temperature of the twin-screw extruder granulator is 150-175°C.

[0037] The internally added polyolefin seven-layer co-extruded light-converting, dust-proof, high heat-insulating, pesticide-resistant, long-acting dripping and fog-eliminating shed film described in the present invention has a thickness ratio of 1:1:1:1:1:1:1:1 among the inner 1 layer, the inner 2 layers, the inner 3 layers, the middle layer, the outer 3 layers, the outer 2 layers, and the outer 1 layer.

[0038] The internally added polyolefin seven-layer co-extruded light-converting, dust-proof, high-insulation, pesticide-resistant, long-acting dripping and fog-eliminating greenhouse film described in the present invention is adjusted in formula and added with dust-proof masterbatch and acid-resistant and aging-resistant masterbatch in the outer layer according to the layered additional functions. After the greenhouse is covered, the outer layer facing the outside of the greenhouse can play the role of self-cleaning and dust-proof, resist light-heat oxidation degradation, and improve the aging resistance function; the light-converting masterbatch and acid-resistant and aging-resistant masterbatch are added to the outer two layers. The main function is to select one or more light-converting agents according to the crop's demand for light quality, and convert the ultraviolet light and green light that are difficult for crops to absorb into blue light and red light with high crop absorption rate to meet the optimal growth action spectrum, so as to adjust and improve the lighting environment in the greenhouse, improve the photosynthetic efficiency of crops, reduce some insect pests, and increase the yield, early maturity and good quality of fruits and vegetables; the outer three layers innovate the dripping agent to guide the inner layer precipitation design scheme, that is, the metallocene resin with higher density is added with hydrotalcite insulation masterbatch and acid-resistant and aging-resistant masterbatch, which plays a role in blocking the outward migration of the dripping agent, which is beneficial to prolonging The drip function is long-lasting, and it also has the function of blocking infrared radiation to the outside of the shed at night and on cloudy days; the middle layer is added with ethylene-vinyl acetate (EVA) resin with a VA content of 19%, hydrotalcite thermal insulation masterbatch, acid-resistant and aging-resistant masterbatch, and drip masterbatch as a drip agent reserve function, while thermal insulation, acid-resistant and aging-resistant; the inner 3 layers are added with EVA resin with a VA content of 14%, hydrotalcite thermal insulation masterbatch and acid-resistant and aging-resistant masterbatch, and drip masterbatch is added as a drip agent reserve Function, at the same time, it plays the insulation function of blocking infrared radiation to the outside of the shed, and it is also resistant to acid and aging; EVA resin with VA content of 12% and hydrotalcite insulation masterbatch, drip masterbatch and defogging masterbatch are added to the inner two layers, which have a slow-release function for the drip and defogging agent, and acid and aging resistant masterbatch is added, which is acid and aging resistant; EVA resin with VA content of 7.5% and drip masterbatch and defogging masterbatch are added to the outer layer, which has the function of controlling the release of drip and defogging agent, and acid and aging resistant masterbatch is added to resist acid and aging.

[0039] The preparation method of the internally added polyolefin seven-layer co-extruded light-converting dust-proof, high heat preservation, pesticide resistance and long-acting dripping and fog-eliminating shed film described in the present invention is as follows: the component materials of the outer 1 layer, the outer 2 layers, the outer 3 layers, the middle layer, the inner 3 layers, the inner 2 layers and the inner 1 layer are respectively mixed and stirred evenly, added into a seven-layer co-extruder, and subjected to melt plasticization blow molding, cooling and shaping, pulling, slitting, edge welding, coding and marking, and winding to obtain the internally added polyolefin seven-layer co-extruded light-converting dust-proof, high heat preservation, pesticide resistance and long-acting dripping and fog-eliminating shed film.

[0040] Wherein: in the seven-layer co-extrusion unit, the extruder temperatures of the outer layer 1, outer layer 2, outer layer 3, middle layer, inner layer 3, inner layer 2 and inner layer 1 are all 150-200°C, the die head temperature is 190-210°C, and the blow-up ratio is 1.5-2.5.

[0041] The internally added polyolefin seven-layer co-extruded light-converting, dust-proof, high-heat-insulating, pesticide-resistant, long-acting dripping and fog-eliminating greenhouse film of the present invention is suitable for preparing covering materials for agricultural facilities.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] (1) The internally-added polyolefin seven-layer co-extruded light-converting, dust-proof, highly heat-insulating, pesticide-resistant, long-lasting anti-dripping and anti-fogging greenhouse film of the present invention has a width of more than 8 m and a thickness of 0.08 mm - 0.15 mm; the light transmittance is more than 90%, and the haze is less than 16%; the infrared transmittance is less than 20%, significantly improving the heat-insulating performance of the greenhouse at night; the light intensity ratio inside and outside the greenhouse is still greater than 88% after 600 days of covering the film; the dust-proof function makes the annual attenuation rate of the light transmittance less than 1.1%; the anti-dripping and anti-fogging function has a long-lasting period of 24 months, synchronized with the life of the film. It can fully meet the requirements of farmers for the performance indicators of the internally-added greenhouse film within a service life of 2 years, saving more greenhouse covering costs and being more low-carbon, green and environmentally friendly.

[0044] (2) For the internally-added polyolefin seven-layer co-extruded light-converting, dust-proof, highly heat-insulating, pesticide-resistant, long-lasting anti-dripping and anti-fogging greenhouse film of the present invention, an innovative design scheme for guiding the internal precipitation of the anti-dripping agent is adopted in the outer three layers, that is, a metallocene resin with a relatively high density is used to add a hydrotalcite heat-insulating masterbatch to increase the density of this layer to play a role in blocking the outward migration of the anti-dripping agent, which is beneficial to extending the long-lasting effect of anti-dripping; in the middle layer and the inner three layers, a composite system of EVA resin with a high VA content and a heat-insulating masterbatch is preferably used to facilitate the accommodation and storage of a sufficient amount of anti-dripping agent and construct a complete concentration gradient of the anti-dripping agent. In the inner two layers and the inner one layer, EVA resins with different VA contents are used to play a role in controlling and slowly releasing the anti-dripping and anti-fogging agent, achieving an excellent anti-dripping and anti-fogging function of the internally-added greenhouse film for 24 months.

[0045] (3) The internally-added polyolefin seven-layer co-extruded light-converting, dust-proof, highly heat-insulating, pesticide-resistant, long-lasting anti-dripping and anti-fogging greenhouse film of the present invention has a function of adjusting and converting the transmitted light wave, realizing the precise optimization of the crop light environment. According to the requirements of crops for light quality, the main absorption peaks of chlorophyll a are blue-violet light at 418 nm and red light at 660 nm; the main absorption peaks of chlorophyll b are blue light at 454 nm and red light at 643 nm; the main absorption of β-carotene is blue-violet light at 400 - 500 nm. Preferably, the light-converting agents green-to-red GTR-650, purple-to-blue VTB440 and purple-to-red VTR660 are selected alone or in combination, so that the greenhouse film has the function of converting part of the green light excitation spectrum of 500 - 580 nm into the red light emission spectrum of 650 nm, which is more beneficial to plant growth, and at the same time converting part of the ultraviolet light excitation spectrum of 290 - 370 nm into the blue light emission spectrum of 440 nm and the red light emission spectrum of 660 nm, enhancing the irradiation intensity of blue light and red light, improving the light environment and light intensity ratio in the greenhouse, and enhancing the photosynthetic efficiency; adding a dust-proof masterbatch reduces the friction coefficient of the film surface, making the greenhouse film as bright as new after being blown by the wind and rained on. Since the irradiation intensity of ultraviolet light UVA is reduced, the occurrence of crop diseases and pests is reduced, the usage amount of pesticides is reduced, and it can make fruits and vegetables mature earlier, increase production and have good quality, and is suitable for covering and cultivating various crops.

[0046] (4) For the internally added polyolefin seven-layer coextruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting dripping and anti-fogging greenhouse film of the present invention, the hindered amine light stabilizers used in the anti-acid and anti-aging masterbatch in the seven-layer formulation are all the compound type of nitrogen-oxyalkyl and nitrogen-alkyl (NOR+NR) 2011AR, which improves the anti-acid performance of the greenhouse film. For Examples 1-5 of the present invention, the anti-S≥3000PPM and Cl≥300PPM are 6 times and 3 times higher than those of Comparative Example 5 of this application with anti-S≤500PPM and Cl≤100PPM, and the anti-acid performance is significantly improved.

[0047] (5) The preparation method of the internally added polyolefin seven-layer coextruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting dripping and anti-fogging greenhouse film of the present invention has a scientific and reasonable hierarchical layout function, avoiding the negative synergistic effect of various functional masterbatches, light conversion agents and dripping agents, with stable and reliable quality and simple and easy operation. Detailed implementation manners

[0048] The present invention will be further described below in conjunction with embodiments.

[0049] Example 1

[0050] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, highly heat-insulating, pesticide-resistant, long-lasting anti-drip and anti-fog greenhouse film described in this Example 1 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1; among them, the outer layer 1 is a dust-proof and anti-aging layer. By mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 80%, acid-resistant and anti-aging masterbatch 10%, and dust-proof masterbatch 10%; the outer layer 2 is a light conversion and anti-aging layer. By mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 21%, linear low-density polyethylene (LLDPE) 15%, metallocene linear low-density polyethylene (mLLDPE) 45%, acid-resistant and anti-aging masterbatch 8%, and light conversion masterbatch 11%; the outer layer 3 is a barrier, heat-insulating, acid-resistant and anti-aging layer. By mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 15%, metallocene linear low-density polyethylene (mLLDPE) 63%, acid-resistant and anti-aging masterbatch 10%, and heat-insulating masterbatch 12%; the middle layer is a highly heat-insulating, acid-resistant and anti-drip agent reserve layer. By mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 62%, acid-resistant and anti-aging masterbatch 8%, anti-drip masterbatch 20%, and heat-insulating masterbatch 10%; the inner layer 3 is a highly heat-insulating, acid-resistant and anti-drip agent reserve layer. By mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 65%, acid-resistant and anti-aging masterbatch 9%, anti-drip masterbatch 17%, and heat-insulating masterbatch 9%; the inner layer 2 is a highly heat-insulating, acid-resistant, anti-drip and anti-fog agent slow-release layer. By mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 67.5%, acid-resistant and anti-aging masterbatch 10%, anti-drip masterbatch 15%, anti-fog masterbatch 1.5%, and heat-insulating masterbatch 6%; the inner layer 1 is an acid-resistant, anti-drip and anti-fog agent release layer. By mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 78%, acid-resistant and anti-aging masterbatch 9%, anti-drip masterbatch 12%, and anti-fog masterbatch 1%.

[0051] Among the raw materials of the outer layer 1: metallocene linear low-density polyethylene (m-LLDPE), the melt index (MI) is 1.0 g / 10 min, the grade is 2010MA, manufactured by ExxonMobil; acid-resistant and anti-aging masterbatch (self-made); the dust-proof masterbatch grade is EFT997, manufactured by Tianjin Riken Co., Ltd.

[0052] The acid-resistant and aging-resistant masterbatch in the outer layer of raw materials includes: 45% low-density polyethylene (LDPE), 40% powdered linear low-density polyethylene (LLDPE), 13% NOR+NR compound light stabilizer, and 2% antioxidant; among them: the brand of low-density polyethylene (LDPE) is 2102TN00, manufactured by Qilu Petrochemical; the brand of powdered low-density linear polyethylene (LLDPE) is 7042, manufactured by Qilu Petrochemical; the brand of light stabilizer is 2011AR, manufactured by BASF; the brand of antioxidant is B215, manufactured by Tianjin Lianlong Company.

[0053] The preparation method of the acid-resistant and aging-resistant masterbatch is as follows: low-density polyethylene (LDPE) 2102TN00, powdered linear low-density polyethylene (LLDPE) 7042, light stabilizer 2011AR and antioxidant B215 are accurately weighed and added into an internal mixer for kneading and plasticization, and then fed into a single-screw extruder granulator through an open mixer, and then hot pelletized and air-cooled and dried to obtain the acid-resistant and aging-resistant masterbatch.

[0054] Wherein: the temperature of the internal mixer is 136±1°C, the plasticizing time is 19±1 minutes, the temperature of each section of the open mixer and the single-screw granulator is 140-170°C (the first zone is 170°C, the second zone is 160°C, and the third zone is 140°C).

[0055] Among the raw materials of the outer two layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D, manufactured by Daqing Petrochemical; linear low-density polyethylene (LLDPE), with a melt index (MI) of 0.85 g / 10 min, brand 9085, manufactured by Tianjin Lianhua; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 1.0 g / 10 min, brand 1018MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made), and light-conversion masterbatch (self-made).

[0056] The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer.

[0057] In terms of mass percentage, the light conversion masterbatch in the outer two layers is composed of the following raw materials: 45% low-density polyethylene (LDPE), 39.6% linear low-density polyethylene (LLDPE), 15% light conversion agent, and 0.4% antioxidant; among which: low-density polyethylene (LDPE) 2102TN00 is manufactured by Qilu Petrochemical; powdered linear low-density polyethylene (LLDPE) 7042 is manufactured by Qilu Petrochemical; the light conversion agent is a compound of green-to-red GTR-650Ⅱ and GTR-650Ⅲ in a mass ratio of 1:1, manufactured by Hunan Xiweier Technology Co., Ltd., and the antioxidant B215 is manufactured by Tianjin Lianlong.

[0058] The preparation method of the light conversion masterbatch is as follows: Accurately measure low-density polyethylene (LDPE) 2102TN00, powdered linear low-density polyethylene (LLDPE) 7042, a compound of light conversion agents green-to-red GTR-650Ⅱ and GTR-650Ⅲ, and antioxidant B215, add them to a kneader in a mixer for kneading and plasticizing, then feed them into a single-screw extruder granulator through a roll mill, perform hot cutting granulation, and enter air-cooling drying to obtain the light conversion masterbatch for standby.

[0059] Among them, the temperature of the kneader in the mixer is 137 ± 1°C, the plasticizing time is 20 minutes, and the temperature of each section is 140 - 170°C (where the first zone is 170°C, the second zone is 160°C, and the third zone is 140°C).

[0060] Among the outer three layers of raw materials: The melt index (MI) of low-density polyethylene (LDPE) is 0.25 g / 10 min, and the grade is 2420D manufactured by Daqing Petrochemical; metallocene linear low-density polyethylene (m-LLDPE), the melt index (MI) is 0.5 g / 10 min, and the grade is 2705MC manufactured by ExxonMobil.

[0061] The raw material composition and preparation method of the acid and aging resistant masterbatch in the outer three layers are exactly the same as those in the outer first layer.

[0062] Calculated by mass percentage, the heat preservation masterbatch in the outer three layers is composed of the following raw materials: low-density polyethylene (LDPE) 20%, linear low-density polyethylene (LLDPE) 16%, hydrotalcite heat preservation agent 60%, coupling agent 2.0%, lubricant 1.0%, dispersant 1.0%; among them: The melt index (MI) of low-density polyethylene (LDPE) is 2.0 g / 10 min, and the grade is 2102TN00 produced by Qilu Petrochemical; the melt index (MI) of linear low-density polyethylene (LLDPE) is 2.0 g / 10 min, and the appearance is powder, and the grade is 7042 produced by Qilu Petrochemical; the hydrotalcite heat preservation agent, the grade is HTP, manufactured by Sakai Chemical Co., Ltd. of Japan; the coupling agent is aluminate, produced by Qingdao Jisi Co., Ltd.; the lubricant is a mixture of zinc stearate and calcium stearate produced by Hebei Zhongshang Chemical Industry with a mass ratio of 1:1; the dispersant is polyethylene wax.

[0063] The preparation method of the heat preservation masterbatch is as follows:

[0064] Accurately measure low-density polyethylene (LDPE) 2102TN00, linear low-density polyethylene (LLDPE) 7042, hydrotalcite heat preservation agent HTP, aluminate coupling agent, mixed lubricant of zinc stearate and calcium stearate, and polyethylene wax dispersant, add them to a kneader in a mixer for kneading and plasticizing, then feed them into a single-screw extruder granulator through a roll mill, perform hot cutting granulation, and enter air-cooling drying to obtain the heat preservation masterbatch for standby.

[0065] The temperature of the internal mixer is 137±1°C, the plasticizing time is 19±1 minutes, and the temperature of each section is 140-170°C (170°C in the first zone, 160°C in the second zone, and 140°C in the third zone).

[0066] The raw materials of the middle layer include: ethylene-vinyl acetate copolymer resin (EVA), VA content of 19%, melt index (MI) of 0.65g / 10min, brand 00119, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the middle layer are exactly the same as those of the outer layer 1; the raw material composition and preparation method of the thermal insulation masterbatch in the middle layer are exactly the same as those of the outer 3 layers.

[0067] In terms of mass percentage, the drip masterbatch of the middle layer is composed of the following raw materials: 40% ethylene vinyl acetate (EVA) resin, 33.5% linear low density polyethylene (LLDPE), 20% drip agent, 0.5% antioxidant, and 6% ultrafine silicon dioxide.

[0068] Wherein: the melt index (MI) of the ethylene-vinyl acetate (EVA) resin in the drip masterbatch is 2.0 g / 10 min, and the VA content is 14% and the grade is 14-2 produced by Beijing Yanshan Organic Chemical; the melt index (MI) of the linear low-density polyethylene (LLDPE) is 2.0 g / 10 min, and the appearance is powder, and the linear low-density polyethylene (LLDPE) is 7042 produced by Qilu Petrochemical; the drip agent grade LD777 is a polyol borate drip agent, produced by Qingdao Siwei Chemical; the antioxidant is B215, and the manufacturer is Tianjin Lianlong Company; the ultrafine silica is produced by Foshan Jinchun and the grade is J430.

[0069] The preparation method of the drip masterbatch is as follows: ethylene vinyl acetate (EVA) resin, linear low-density polyethylene (LLDPE), drip agent, antioxidant and ultrafine silica are added into a high-speed mixer according to proportion and kneaded, and then the kneaded material is fed into a twin-screw extruder granulator, and the drip masterbatch is obtained after drawing, water cooling, pelletizing, drying and cooling.

[0070] Wherein: the temperature of the high-speed mixer is 80°C, the kneading time is 13 minutes, and the temperature of the twin-screw extruder granulator is 150-175°C, wherein: zone 1 is 150°C, zone 2 is 165°C, zone 3 is 175°C, and zone 4 is 175°C.

[0071] The raw materials of the inner three layers are: ethylene-vinyl acetate copolymer resin (EVA), VA content 14%, melt index (MI) 0.25g / 10min, brand FL00014, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner three layers are exactly the same as those of the outer one layer; the raw material composition and preparation method of the thermal insulation masterbatch in the inner three layers are exactly the same as those of the outer three layers. The raw material composition and preparation method of the drip masterbatch in the inner three layers are exactly the same as those of the middle layer.

[0072] The raw materials of the inner 2 layers are: ethylene-vinyl acetate copolymer resin (EVA), VA content 12%, melt index (MI) 0.5g / 10min, brand FL00012, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner 2 layers are exactly the same as those of the outer 1 layer; the raw material composition and preparation method of the thermal insulation masterbatch in the inner 2 layers are exactly the same as those of the outer 3 layers. The raw material composition and preparation method of the drip masterbatch in the inner 2 layers are exactly the same as those of the middle layer.

[0073] Calculated by mass percentage, the defogging masterbatch in the inner two layers is composed of the following raw materials: 50% ethylene vinyl acetate (EVA) resin, 39.8% linear low-density polyethylene (LLDPE), 10% defogging agent, and 0.2% antioxidant.

[0074] Among them: the melt index (MI) of the ethylene-vinyl acetate (EVA) resin in the defogging masterbatch is 2.0g / 10min, and the VA content is 14% and the grade is 14-2 produced by Beijing Yanshan Organic Chemical; the melt index (MI) of the linear low-density polyethylene (LLDPE) is 2.0g / 10min, and the linear low-density polyethylene (LLDPE) is 7042 produced by Qilu Petrochemical; the defogging agent TS403 is produced by Dalian Jinlong; the antioxidant is B215 produced by Tianjin Lianlong Company.

[0075] The preparation method of the defogging masterbatch is as follows: ethylene vinyl acetate (EVA) resin, linear low-density polyethylene (LLDPE), defogging agent and antioxidant are added into a high-speed mixer according to proportion and kneaded, and then the kneaded material is fed into a twin-screw extruder granulator, and then the defogging masterbatch is obtained after being drawn, water-cooled, pelletized, and entered into a drying device and cooled.

[0076] Wherein: the temperature of the high-speed mixer is 80°C, the kneading time is 13 minutes, and the temperature of the twin-screw extruder granulator is 150-175°C, wherein: zone 1 is 150°C, zone 2 is 165°C, zone 3 is 175°C, and zone 4 is 175°C.

[0077] The raw materials of the inner layer 1 are: ethylene-vinyl acetate copolymer resin (EVA), VA content 7.5%, melt index (MI) 0.5g / 10min, brand 00111, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner layer 1 are exactly the same as those of the outer layer 1. The raw material composition and preparation method of the drip masterbatch in the inner layer 1 are exactly the same as those of the middle layer. The raw material composition and preparation method of the defogging masterbatch in the inner layer 1 are exactly the same as those of the inner layer 2.

[0078] The preparation method of the internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting dripping and anti-fogging greenhouse film in Example 1 is as follows: The components of the outer 1 layer, outer 2 layer, outer 3 layer, middle layer, inner 3 layer, inner 2 layer and inner 1 layer are respectively mixed and stirred evenly, and then added into a seven-layer co-extrusion extruder. After melting, plasticizing, blow molding, cooling and shaping, traction, corona treatment, dipping in coating solution, drying, edge welding, slitting, inkjet marking and winding, the internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting dripping and anti-fogging greenhouse film is obtained.

[0079] The product specifications of the prepared product are 12000 / 0.12mm, and the designed service life is 2 years; the layer thickness ratio of the outer 1 layer, outer 2 layer, outer 3 layer, middle layer, inner 3 layer, inner 2 layer and inner 1 layer is 1:1:1:1:1:1:1; the blow-up ratio is 1.75. In the seven-layer co-extrusion unit, the temperature process conditions of the inner 1 layer, inner 2 layer, inner 3 layer, middle layer, outer 3 layer, outer 2 layer, outer 1 layer extruders, machine necks, die heads, die head bottoms and die rings, and each zone of the oven are shown in Table 1 in detail.

[0080] Table 1 Preparation process conditions of Example 1

[0081]

[0082]

[0083] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting dripping and anti-fogging greenhouse film prepared in Example 1 has a light transmittance of 90.3%, a haze of 15.2%, and a continuous period of the dripping and anti-fogging function of 2 years. By adding the light conversion agent GTR650, the greenhouse film has the function of exciting part of the green light spectrum at 580nm and converting it into the red light emission spectrum at 650nm, which is more beneficial to plant growth, improving the light environment in the greenhouse, so that the fruits color quickly, have a high vitamin C content and good taste quality; by adding the dust-proof masterbatch, the surface friction coefficient of the greenhouse film is reduced to 0.10, and it remains as bright as new after being blown by the wind and washed by the rain, and the light transmittance attenuation is not obvious; by adding the high heat-insulating resin EVA and the heat-insulating masterbatch, they act as carriers for the storage and slow release of the dripping agent, and make the transmittance of infrared rays radiated outward from the greenhouse at night low. The greenhouse film prepared in Example 1 was used to cover and plant sweet peppers (Kaitelin) in the experimental base of Shandong Agricultural University in Lujiazhuang, Fangxia Town, Laiwu in October 2022, and the yield increased by 27.6% and the picking was advanced by 7 days. The greenhouse film prepared in Example 1 was determined to be a special film for sweet peppers through expert yield measurement and evaluation. Example 1 was also verified by greenhouse covering demonstration and was suitable for covering crops such as eggplants, zucchinis, Nina Queen and Crimson Seedless grapes.

[0084] Example 2

[0085] The inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, long-lasting anti-pesticide, long-lasting dripping and anti-fogging greenhouse film described in this Example 2 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1; among them, the outer layer 1 is a dust-proof and anti-aging layer. By mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 82%, acid-resistant and anti-aging masterbatch 9%, and dust-proof masterbatch 9%; the outer layer 2 is a light conversion and anti-aging layer. By mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 23%, linear low-density polyethylene (LLDPE) 17%, metallocene linear low-density polyethylene (mLLDPE) 40%, acid-resistant and anti-aging masterbatch 10%, and light conversion masterbatch 10%; the outer layer 3 is a barrier, heat-insulating, acid-resistant and anti-aging layer. By mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 20%, metallocene linear low-density polyethylene (mLLDPE) 60%, acid-resistant and anti-aging masterbatch 9%, and heat-insulating masterbatch 11%; the middle layer is a high heat-insulating, acid-resistant and dripping agent reserve layer. By mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 62%, acid-resistant and anti-aging masterbatch 9%, dripping masterbatch 20%, and heat-insulating masterbatch 9%; the inner layer 3 is a high heat-insulating, acid-resistant and dripping agent reserve layer. By mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 66%, acid-resistant and anti-aging masterbatch 8%, dripping masterbatch 17%, and heat-insulating masterbatch 9%; the inner layer 2 is a high heat-insulating, acid-resistant, dripping and anti-fogging agent slow-release layer. By mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 68.5%, acid-resistant and anti-aging masterbatch 9%, dripping masterbatch 14%, anti-fogging masterbatch 1.5%, and heat-insulating masterbatch 7%; the inner layer 1 is an acid-resistant, dripping and anti-fogging agent release layer. By mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 79%, acid-resistant and anti-aging masterbatch 9%, dripping masterbatch 11%, and anti-fogging masterbatch 1%.

[0086] Among the raw materials of the outer layer 1: Metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 1.0 g / 10 min, grade 2010MA, manufactured by ExxonMobil; Acid-resistant and anti-aging masterbatch (self-made); The dust-proof masterbatch has the grade EFT997 and is manufactured by Tianjin Riken Co., Ltd.

[0087] The raw material composition and preparation process method of the acid-resistant and anti-aging masterbatch are exactly the same as those of the outer layer 1 in Example 1.

[0088] Among the raw materials of the outer two layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D, manufactured by Daqing Petrochemical; linear low-density polyethylene (LLDPE), with a melt index (MI) of 0.85 g / 10 min, brand 9085, manufactured by Tianjin Lianhua; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 1.0 g / 10 min, brand 1018MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made), and light-conversion masterbatch (self-made).

[0089] The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer 1 in Example 1.

[0090] In terms of mass percentage, the light conversion masterbatch in the outer two layers is composed of the following raw materials: 45% low-density polyethylene (LDPE), 39.6% linear low-density polyethylene (LLDPE), 15% light conversion agent, and 0.4% antioxidant; among them: low-density polyethylene (LDPE) 2102TN00 is manufactured by Qilu Petrochemical; powdered linear low-density polyethylene (LLDPE) 7042 is manufactured by Qilu Petrochemical; the light conversion agent is green-to-red GTR-650Ⅱ and GTR-650Ⅲ, purple-to-red VTR660, and purple-to-blue VTB440, which are compounded in a mass ratio of 3:2:2:3 and manufactured by Hunan Xiweier Technology Co., Ltd., and the antioxidant B215 is manufactured by Tianjin Lianlong.

[0091] The preparation method of the light conversion masterbatch is exactly the same as that of the outer two layers in Example 1.

[0092] Among the raw materials of the outer three layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D manufactured by Daqing Petrochemical; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 0.5 g / 10 min, brand 2705MC manufactured by ExxonMobil.

[0093] The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the outer three layers are exactly the same as those of the outer one layer in Example 1.

[0094] The raw material composition and preparation method of the thermal insulation masterbatch in the outer three layers are exactly the same as those of the outer three layers in Example 1.

[0095] The raw materials of the middle layer include: ethylene-vinyl acetate copolymer resin (EVA), VA content 19%, melt index (MI) 0.65g / 10min, brand 00119, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the middle layer are exactly the same as those of the outer layer 1 in Example 1; the raw material composition and preparation method of the thermal insulation masterbatch in the middle layer are exactly the same as those of the outer 3 layers in Example 1. The raw material composition and preparation method of the drip masterbatch in the middle layer are exactly the same as those of the middle layer in Example 1.

[0096] Among the raw materials of the inner three layers: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 14%, a melt index (MI) of 0.25 g / 10 min, grade FL00014, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner three layers are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the heat-insulating masterbatch in the inner three layers are exactly the same as those of the outer third layer in Example 1. The raw material composition and preparation method of the anti-dripping masterbatch in the inner three layers are exactly the same as those of the middle layer in Example 1.

[0097] Among the raw materials of the inner two layers: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 12%, a melt index (MI) of 0.5 g / 10 min, grade FL00012, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner two layers are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the heat-insulating masterbatch in the inner two layers are exactly the same as those of the outer third layer in Example 1. The raw material composition and preparation method of the anti-dripping masterbatch in the inner two layers are exactly the same as those of the middle layer in Example 1. The raw material composition and preparation method of the anti-fog masterbatch in the inner two layers are exactly the same as those of the inner second layer in Example 1.

[0098] Among the raw materials of the inner first layer: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 7.5%, a melt index (MI) of 0.5 g / 10 min, grade 00111, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner first layer are exactly the same as those of the outer first layer in Example 1. The raw material composition and preparation method of the anti-dripping masterbatch in the inner first layer are exactly the same as those of the middle layer in Example 1. The raw material composition and preparation method of the anti-fog masterbatch in the inner first layer are exactly the same as those of the inner second layer in Example 1.

[0099] The preparation method and process conditions of the inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting anti-dripping and anti-fog greenhouse film described in this Example 2 are exactly the same as those in Example 1.

[0100] The internally added polyolefin seven-layer coextruded light conversion, dust-proof, highly heat-insulating, long-lasting pesticide-resistant, long-lasting anti-dripping and anti-fogging greenhouse film prepared in Example 2 has a product specification of 12000 / 0.12 mm; the designed service life is 2 years. The light transmittance is 90.7%, the haze is 15.7%, and the duration of the anti-dripping and anti-fogging function is verified to be 24 months after covering the greenhouse. The light conversion agents added are the compound of green-to-red GTR-650Ⅱ+Ⅲ, purple-to-blue VTB440, and purple-to-red VTR660, enabling the greenhouse film to have the function of converting part of the green light excitation spectrum of 500 - 580 nm into the red light emission spectrum of 650 nm, which is more beneficial to plant growth, and at the same time converting part of the ultraviolet light excitation spectrum of 290 - 370 nm into the blue light emission spectrum of 440 nm and the red light emission spectrum of 660 nm, enhancing the irradiation intensity of blue light and red light, improving the light environment in the greenhouse, increasing the vitamin C content, having good coloring, and high yield; adding a dust-proof masterbatch makes the greenhouse film as bright as new after being exposed to wind and rain, and the decrease in light transmittance is not obvious. Adding high heat-insulating resin EVA and a heat-insulating masterbatch serves as a reserve and slow-release carrier for the anti-dripping agent, and makes the transmittance of infrared rays radiated outward from the greenhouse at night low. The greenhouse film prepared in Example 2 was applied in the field demonstration at the experimental base of Shandong Agricultural University in Gaozhuang, Fangxia Town, Laiwu in October 2022. The yield of strawberries (Tianbao) planted increased by 25.60%, the picking was advanced by 9 days, and the percentage of big red fruits was high, with good taste, high sugar content, and good quality. The greenhouse film prepared in Example 2 was determined to be a special film for strawberries by expert evaluation. It is also suitable for covering and planting cherries, blueberries, etc.

[0101] Example 3

[0102] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high-insulation, long-lasting anti-pesticide, long-lasting dripping and anti-fog greenhouse film described in this Example 3 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1; among them, the outer layer 1 is a dust-proof and anti-aging layer. In terms of mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 83%, acid-resistant and anti-aging masterbatch 9%, and dust-proof masterbatch 8%; the outer layer 2 is a light conversion and anti-aging layer. In terms of mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 25%, linear low-density polyethylene (LLDPE) 15%, metallocene linear low-density polyethylene (mLLDPE) 42%, acid-resistant and anti-aging masterbatch 9%, and light conversion masterbatch 9%; the outer layer 3 is a barrier, heat-insulating, acid-resistant and anti-aging layer. In terms of mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 22%, metallocene linear low-density polyethylene (mLLDPE) 60%, acid-resistant and anti-aging masterbatch 8%, and heat-insulating masterbatch 10%; the middle layer is a high-insulation, acid-resistant, and dripping agent reserve layer. In terms of mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 60%, acid-resistant and anti-aging masterbatch 10%, dripping agent masterbatch 20%, and heat-insulating masterbatch 10%; the inner layer 3 is a high-insulation, acid-resistant, and dripping agent reserve layer. In terms of mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 63%, acid-resistant and anti-aging masterbatch 9%, dripping agent masterbatch 18%, and heat-insulating masterbatch 10%; the inner layer 2 is a high-insulation, acid-resistant, dripping and anti-fog agent slow-release layer. In terms of mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 69.5%, acid-resistant and anti-aging masterbatch 8%, dripping agent masterbatch 15%, anti-fog masterbatch 1.5%, and heat-insulating masterbatch 6%; the inner layer 1 is an acid-resistant, dripping and anti-fog agent release layer. In terms of mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 80%, acid-resistant and anti-aging masterbatch 8%, dripping agent masterbatch 11%, and anti-fog masterbatch 1%.

[0103] Among the raw materials of the outer layer 1: metallocene linear low-density polyethylene (m-LLDPE), the melt index (MI) is 1.0 g / 10 min, the grade is 2010MA, manufactured by ExxonMobil; acid-resistant and anti-aging masterbatch (self-made); the dust-proof masterbatch grade is EFT997, manufactured by Tianjin Riken Co., Ltd.

[0104] The raw material composition and preparation process method of the acid-resistant and anti-aging masterbatch are exactly the same as those of the outer layer 1 in Example 1.

[0105] Among the raw materials of the outer two layers: the melt index (MI) of low-density polyethylene (LDPE) is 0.25g / 10min, the brand is 2420D, manufactured by Daqing Petrochemical; the linear low-density polyethylene (LLDPE) has a melt index (MI) of 0.85g / 10min, the brand is 9085, manufactured by Tianjin Lianhua; the metallocene linear low-density polyethylene (m-LLDPE) has a melt index (MI) of 1.0g / 10min, the brand is 1018MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made), light-conversion masterbatch (self-made); the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer of Example 1.

[0106] In terms of mass percentage, the light conversion masterbatch in the outer two layers is composed of the following raw materials: 45% low-density polyethylene (LDPE), 39.6% linear low-density polyethylene (LLDPE), 15% light conversion agent, and 0.4% antioxidant; among which: low-density polyethylene (LDPE) 2102TN00 is manufactured by Qilu Petrochemical; powdered linear low-density polyethylene (LLDPE) 7042 is manufactured by Qilu Petrochemical; the light conversion agent is green-to-red GTR-650Ⅱ and GTR-650Ⅲ, purple-to-red VTR660, and purple-to-blue VTB440, compounded in a mass ratio of 3:3:2:2, manufactured by Hunan Xiweier Technology Co., Ltd., and the antioxidant B215 is manufactured by Tianjin Lianlong.

[0107] The preparation method of the light conversion masterbatch is exactly the same as that of the outer two layers in Example 1.

[0108] Among the raw materials of the outer three layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D manufactured by Daqing Petrochemical; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 0.5 g / 10 min, brand 2705MC manufactured by ExxonMobil. The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the outer three layers are exactly the same as those of the outer layer 1 in Example 1. The raw material composition and preparation method of the thermal insulation masterbatch in the outer three layers are exactly the same as those of the outer three layers in Example 1.

[0109] The raw materials of the middle layer: ethylene-vinyl acetate copolymer resin (EVA), VA content 19%, melt index (MI) 0.65g / 10min, brand 00119, produced by ExxonMobil; drip masterbatch brand EFT641 (drip agent KF650 content 20%), manufactured by Tianjin Riken Kaisha; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the middle layer are exactly the same as those of the outer layer 1 in Example 1; the raw material composition and preparation method of the thermal insulation masterbatch in the middle layer are exactly the same as those of the outer 3 layers in Example 1. The raw material composition and preparation method of the drip masterbatch in the middle layer are exactly the same as those of the middle layer in Example 1.

[0110] Among the raw materials of the inner three layers: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 14%, a melt index (MI) of 0.25 g / 10 min, grade FL00014, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner three layers are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the heat-insulating masterbatch in the inner three layers are exactly the same as those of the outer third layer in Example 1; the raw material composition and preparation method of the anti-dripping masterbatch in the inner three layers are exactly the same as those of the middle layer in Example 1.

[0111] Among the raw materials of the inner two layers: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 12%, a melt index (MI) of 0.5 g / 10 min, grade FL00012, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner two layers are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the heat-insulating masterbatch in the inner two layers are exactly the same as those of the outer third layer in Example 1; the raw material composition and preparation method of the anti-dripping masterbatch in the inner two layers are exactly the same as those of the middle layer in Example 1; the raw material composition and preparation method of the anti-fogging masterbatch in the inner two layers are exactly the same as those of the inner second layer in Example 1.

[0112] Among the raw materials of the inner first layer: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 7.5%, a melt index (MI) of 0.5 g / 10 min, grade 00111, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the inner first layer are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the anti-dripping masterbatch in the inner first layer are exactly the same as those of the middle layer in Example 1; the raw material composition and preparation method of the anti-fogging masterbatch in the inner first layer are exactly the same as those of the inner second layer in Example 1.

[0113] The preparation method and process conditions of the inner-added polyolefin seven-layer coextruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting anti-dripping and anti-fogging greenhouse film described in this Example 3 are exactly the same as those in Example 1.

[0114] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, highly heat-insulating, long-lasting anti-pesticide, drip and fog-eliminating greenhouse film prepared in Example 3 has a product specification of 12000 / 0.12 mm; the designed service life is 2 years. The light transmittance is 90.5%, and the haze is 15.6%. After the greenhouse covering verification, the duration of the drip and fog-eliminating function is 24 months. The light conversion agents added are the compound of green-to-red GTR-650Ⅱ+Ⅲ, purple-to-blue VTB440 and purple-to-red VTR660, enabling the greenhouse film to have the function of converting part of the green light excitation spectrum of 500 - 580 nm into the red light emission spectrum of 650 nm, which is more beneficial to plant growth, and at the same time converting part of the ultraviolet light excitation spectrum of 290 - 370 nm into the blue light emission spectrum of 440 nm and the red light emission spectrum of 660 nm, enhancing the irradiation intensity of blue light and red light, improving the light environment in the greenhouse, increasing the vitamin C content, having good coloring, and high yield; adding the dust-proof masterbatch makes the greenhouse film as bright as new after being exposed to wind and rain, and the decrease in light transmittance is not obvious. The high heat-insulating resin EVA and the heat-insulating masterbatch are added to serve as the reserve and slow-release carrier of the drip agent, and make the transmittance of the infrared rays radiated outward from the greenhouse at night low. The greenhouse film prepared in Example 3 was applied and demonstrated in the field of the experimental base of Shandong Agricultural University in Gaozhuang, Fangxia Town, Laiwu in October 2022. The yield of the planted tomatoes (Pioneer No. 4) increased by 25.30%, the picking was advanced by 7 days, and the percentage of big red fruits of the fruits was high, with good taste, high sugar content and good quality. The greenhouse film prepared in Example 3 was determined as a special film for tomatoes by expert evaluation. It is also suitable for covering and planting cucumbers, bitter gourds, melons, watermelons, winter jujubes, etc.

[0115] Example 4

[0116] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, highly heat-insulating, pesticide-resistant, long-lasting dripping and fog-eliminating greenhouse film described in this Example 4 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1; among them, the outer layer 1 is a dust-proof and aging-resistant layer. By mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 84%, acid-resistant and aging-resistant masterbatch 8%, and dust-proof masterbatch 8%; the outer layer 2 is a light conversion and aging-resistant layer. By mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 28%, linear low-density polyethylene (LLDPE) 16%, metallocene linear low-density polyethylene (mLLDPE) 35%, acid-resistant and aging-resistant masterbatch 11%, and light conversion masterbatch 10%; the outer layer 3 is a barrier, heat-insulating, acid-resistant and aging-resistant layer. By mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 18%, metallocene linear low-density polyethylene (mLLDPE) 62%, acid-resistant and aging-resistant masterbatch 10%, and heat-insulating masterbatch 10%; the middle layer is a highly heat-insulating, acid-resistant, and dripping agent reserve layer. By mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 59%, acid-resistant and aging-resistant masterbatch 9%, dripping masterbatch 21%, and heat-insulating masterbatch 11%; the inner layer 3 is a highly heat-insulating, acid-resistant, and dripping agent reserve layer. By mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 66%, acid-resistant and aging-resistant masterbatch 8%, dripping masterbatch 16%, and heat-insulating masterbatch 10%; the inner layer 2 is a highly heat-insulating, acid-resistant, dripping and fog-eliminating agent slow-release layer. By mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 69.5%, acid-resistant and aging-resistant masterbatch 9%, dripping masterbatch 14%, fog-eliminating masterbatch 1.5%, and heat-insulating masterbatch 6%; the inner layer 1 is an acid-resistant, dripping and fog-eliminating agent release layer. By mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 79%, acid-resistant and aging-resistant masterbatch 9%, dripping masterbatch 11%, and fog-eliminating masterbatch 1%.

[0117] Among the raw materials of the outer layer 1: metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 1.0 g / 10 min, grade 2010MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made); the dust-proof masterbatch has the grade EFT997 and is manufactured by Tianjin Riken Co., Ltd.

[0118] The raw material composition and preparation process method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer 1 in Example 1.

[0119] Among the raw materials of the outer two layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D, manufactured by Daqing Petrochemical; linear low-density polyethylene (LLDPE), with a melt index (MI) of 0.85 g / 10 min, brand 9085, manufactured by Tianjin Lianhua; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 1.0 g / 10 min, brand 1018MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made), and light-conversion masterbatch (self-made).

[0120] The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer 1 in Example 1.

[0121] In terms of mass percentage, the light conversion masterbatch in the outer two layers is composed of the following raw materials: 45% low-density polyethylene (LDPE), 39.6% linear low-density polyethylene (LLDPE), 15% light conversion agent, and 0.4% antioxidant; among them: low-density polyethylene (LDPE) 2102TN00 is manufactured by Qilu Petrochemical; powdered linear low-density polyethylene (LLDPE) 7042 is manufactured by Qilu Petrochemical; the light conversion agent is green-to-red GTR-650Ⅱ and GTR-650Ⅲ, purple-to-red VTR660, and purple-to-blue VTB440, which are compounded in a mass ratio of 3:2:2:3 and manufactured by Hunan Xiweier Technology Co., Ltd., and the antioxidant B215 is manufactured by Tianjin Lianlong.

[0122] The preparation method of the light conversion masterbatch is exactly the same as that of the outer two layers in Example 1.

[0123] Among the raw materials of the outer three layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D manufactured by Daqing Petrochemical; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 0.5 g / 10 min, brand 2705MC manufactured by ExxonMobil. The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the outer three layers are exactly the same as those of the outer layer 1 in Example 1. The raw material composition and preparation method of the thermal insulation masterbatch in the outer three layers are exactly the same as those of the outer three layers in Example 1.

[0124] The raw materials of the middle layer include: ethylene-vinyl acetate copolymer resin (EVA), VA content 19%, melt index (MI) 0.65g / 10min, brand 00119, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the middle layer are exactly the same as those of the outer layer 1 in Example 1; the raw material composition and preparation method of the thermal insulation masterbatch in the middle layer are exactly the same as those of the outer 3 layers in Example 1. The raw material composition and preparation method of the drip masterbatch in the middle layer are exactly the same as those of the middle layer in Example 1.

[0125] Among the raw materials of the inner three layers: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 14%, a melt index (MI) of 0.25 g / 10 min, grade FL00014, produced by ExxonMobil; the raw material composition and preparation method of the acid and aging resistant masterbatch in the inner three layers are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the heat preservation masterbatch in the inner three layers are exactly the same as those of the outer third layer in Example 1; the raw material composition and preparation method of the anti-dripping masterbatch in the inner three layers are exactly the same as those of the middle layer in Example 1.

[0126] Among the raw materials of the inner two layers: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 12%, a melt index (MI) of 0.5 g / 10 min, grade FL00012, produced by ExxonMobil; the raw material composition and preparation method of the acid and aging resistant masterbatch in the inner two layers are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the heat preservation masterbatch in the inner two layers are exactly the same as those of the outer third layer in Example 1; the raw material composition and preparation method of the anti-dripping masterbatch in the inner two layers are exactly the same as those of the middle layer in Example 1; the raw material composition and preparation method of the anti-fog masterbatch in the inner two layers are exactly the same as those of the inner second layer in Example 1.

[0127] Among the raw materials of the inner first layer: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 7.5%, a melt index (MI) of 0.5 g / 10 min, grade 00111, produced by ExxonMobil; the raw material composition and preparation method of the acid and aging resistant masterbatch in the inner first layer are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the anti-dripping masterbatch in the inner second layer are exactly the same as those of the middle layer in Example 1; the raw material composition and preparation method of the anti-fog masterbatch in the inner second layer are exactly the same as those of the inner second layer in Example 1.

[0128] The preparation method and process conditions of the inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat preservation, anti-pesticide, long-lasting anti-dripping and anti-fog greenhouse film described in this Example 4 are exactly the same as those in Example 1.

[0129] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, long-lasting anti-pesticide, dripping and fog-eliminating greenhouse film prepared in Example 4 has a product specification of 12000 / 0.12 mm; the designed service life is 2 years. The light transmittance is 90.8%, and the haze is 15.3%. After the greenhouse covering verification, the duration of the dripping and fog-eliminating function is 24 months. The added light conversion agents are the compound of green-to-red GTR-650Ⅱ+Ⅲ, purple-to-blue VTB440 and purple-to-red VTR660, enabling the greenhouse film to have the function of converting part of the green light excitation spectrum of 500-580 nm into the red light emission spectrum of 650 nm, which is more beneficial to plant growth, and at the same time converting part of the ultraviolet light excitation spectrum of 290-370 nm into the blue light emission spectrum of 440 nm and the red light emission spectrum of 660 nm, enhancing the irradiation intensity of blue light and red light, improving the lighting environment in the greenhouse, increasing the vitamin C content, having good coloring and high yield; the added dust-proof masterbatch makes the greenhouse film as bright as new after being exposed to wind and rain, and the decrease in light transmittance is not obvious. The high heat-insulating resin EVA and the heat-insulating masterbatch are added to serve as the storage and slow-release carrier of the dripping agent, and make the transmittance of the infrared rays radiated outward from the greenhouse at night low. The greenhouse film prepared in Example 4 was applied and demonstrated in the greenhouse of Shandong Agricultural University in Gaozhuang, Laiwu in October 2022. The yield of the planted blueberries increased by 18.3%, the picking was advanced by 10 days, and the fruits were large, bright in color and good in taste and quality. The greenhouse film prepared in Example 4 was determined to be a special film for blueberries by expert evaluation.

[0130] Example 5

[0131] The internally added polyolefin seven-layer coextruded light conversion, dust-proof, high heat-insulating, long-lasting pesticide-resistant, long-lasting anti-drip and anti-fog greenhouse film described in this Example 5 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1. Among them, the outer layer 1 is a dust-proof and aging-resistant layer. Calculated by mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 83%, acid-resistant and aging-resistant masterbatch 8%, and dust-proof masterbatch 9%. The outer layer 2 is a light conversion and aging-resistant layer. Calculated by mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 24%, linear low-density polyethylene (LLDPE) 20%, metallocene linear low-density polyethylene (mLLDPE) 35%, acid-resistant and aging-resistant masterbatch 10%, and light conversion masterbatch 11%. The outer layer 3 is a barrier, heat-insulating, acid-resistant and aging-resistant layer. Calculated by mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 16%, metallocene linear low-density polyethylene (mLLDPE) 63%, acid-resistant and aging-resistant masterbatch 9%, and heat-insulating masterbatch 12%. The middle layer is a high heat-insulating, acid-resistant anti-drip agent reserve layer. Calculated by mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 62%, acid-resistant and aging-resistant masterbatch 8%, anti-drip masterbatch 21%, and heat-insulating masterbatch 9%. The inner layer 3 is a high heat-insulating, acid-resistant anti-drip agent reserve layer. Calculated by mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 65%, acid-resistant and aging-resistant masterbatch 9%, anti-drip masterbatch 17%, and heat-insulating masterbatch 9%. The inner layer 2 is a high heat-insulating, acid-resistant anti-drip and anti-fog agent slow-release layer. Calculated by mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 68.5%, acid-resistant and aging-resistant masterbatch 9%, anti-drip masterbatch 15%, anti-fog masterbatch 1.5%, and heat-insulating masterbatch 6%. The inner layer 1 is an acid-resistant anti-drip and anti-fog agent release layer. Calculated by mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 79%, acid-resistant and aging-resistant masterbatch 9%, anti-drip masterbatch 11%, and anti-fog masterbatch 1%.

[0132] Among the raw materials of the outer layer 1: metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 1.0 g / 10 min, grade 2010MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made); dust-proof masterbatch, grade EFT997, manufactured by Tianjin Riken Co., Ltd.

[0133] The raw material composition and preparation process method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer 1 in Example 1.

[0134] Among the raw materials of the outer two layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D, manufactured by Daqing Petrochemical; linear low-density polyethylene (LLDPE), with a melt index (MI) of 0.85 g / 10 min, brand 9085, manufactured by Tianjin Lianhua; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 1.0 g / 10 min, brand 1018MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made), and light-conversion masterbatch (self-made).

[0135] The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer 1 in Example 1.

[0136] In terms of mass percentage, the light conversion masterbatch in the outer two layers is composed of the following raw materials: 45% low-density polyethylene (LDPE), 39.6% linear low-density polyethylene (LLDPE), 15% light conversion agent, and 0.4% antioxidant; among which: low-density polyethylene (LDPE) 2102TN00 is manufactured by Qilu Petrochemical; powdered linear low-density polyethylene (LLDPE) 7042 is manufactured by Qilu Petrochemical; the light conversion agent is purple-to-red VTR660 and purple-to-blue VTB440, compounded in a mass ratio of 2:3, manufactured by Hunan Xiweier Technology Co., Ltd., and the antioxidant B215 is manufactured by Tianjin Lianlong.

[0137] The preparation method of the light conversion masterbatch is exactly the same as that of the outer two layers in Example 1.

[0138] Among the raw materials of the outer three layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D manufactured by Daqing Petrochemical; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 0.5 g / 10 min, brand 2705MC manufactured by ExxonMobil. The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the outer three layers are exactly the same as those of the outer layer 1 in Example 1. The raw material composition and preparation method of the thermal insulation masterbatch in the outer three layers are exactly the same as those of the outer three layers in Example 1.

[0139] The raw materials of the middle layer include: ethylene-vinyl acetate copolymer resin (EVA), VA content 19%, melt index (MI) 0.65g / 10min, brand 00119, produced by ExxonMobil; the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch in the middle layer are exactly the same as those of the outer layer 1 in Example 1; the raw material composition and preparation method of the thermal insulation masterbatch in the middle layer are exactly the same as those of the outer 3 layers in Example 1. The raw material composition and preparation method of the drip masterbatch in the middle layer are exactly the same as those of the middle layer in Example 1.

[0140] Among the raw materials of the inner three layers: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 14%, a melt index (MI) of 0.25 g / 10 min, grade FL00014, produced by ExxonMobil; the raw material composition and preparation method of the acid and aging resistant masterbatch in the inner three layers are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the heat preservation masterbatch in the inner three layers are exactly the same as those of the outer third layer in Example 1; the raw material composition and preparation method of the anti-drip masterbatch in the inner three layers are exactly the same as those of the middle layer in Example 1.

[0141] Among the raw materials of the inner two layers: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 12%, a melt index (MI) of 0.5 g / 10 min, grade FL00012, produced by ExxonMobil; the raw material composition and preparation method of the acid and aging resistant masterbatch in the inner two layers are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the heat preservation masterbatch in the inner two layers are exactly the same as those of the outer third layer in Example 1; the raw material composition and preparation method of the anti-drip masterbatch in the inner two layers are exactly the same as those of the middle layer in Example 1; the raw material composition and preparation method of the anti-fog masterbatch in the inner two layers are exactly the same as those of the inner second layer in Example 1.

[0142] Among the raw materials of the inner first layer: ethylene-vinyl acetate copolymer resin (EVA), with a VA content of 7.5%, a melt index (MI) of 0.5 g / 10 min, grade 00111, produced by ExxonMobil; the raw material composition and preparation method of the acid and aging resistant masterbatch in the inner first layer are exactly the same as those of the outer first layer in Example 1; the raw material composition and preparation method of the anti-drip masterbatch in the inner first layer are exactly the same as those of the middle layer in Example 1; the raw material composition and preparation method of the anti-fog masterbatch in the inner first layer are exactly the same as those of the inner second layer in Example 1.

[0143] The preparation method and process conditions of the inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat preservation, anti-pesticide, long-lasting anti-drip and anti-fog greenhouse film described in this Example 5 are exactly the same as those in Example 1.

[0144] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high-insulation, long-lasting anti-pesticide, long-lasting dripping and anti-fogging greenhouse film prepared in Example 5 has a product specification of 12000 / 0.12 mm; the designed service life is 2 years. The light transmittance is 90.8%, and the haze is 15.6%. After greenhouse covering verification, the duration of the dripping and anti-fogging function is 24 months. The added light conversion agents are the compound of violet-to-blue VTB440 and violet-to-red VTR660, which endow the greenhouse film with the function of converting part of the ultraviolet light excitation spectrum of 290 - 370 nm into the blue light emission spectrum of 440 nm and the red light emission spectrum of 660 nm, enhancing the irradiation intensity of blue light and red light, improving the lighting environment in the greenhouse, being suitable for covering tobacco and rice seedling raising, and also suitable for covering all green leafy vegetables, making the stems thick and the leaves plump, with high yield and good quality. The added dust-proof masterbatch makes the greenhouse film as bright as new after being exposed to wind and rain, and the decrease in light transmittance is not obvious. The high-insulation resin EVA and the insulation masterbatch are added to serve as the reserve and slow-release carrier of the dripping agent, and the transmittance of infrared rays radiated outward from the greenhouse at night is low; the greenhouse film prepared in Example 5 has been used for field application greenhouse covering demonstrations in Hunan, Hubei and Fujian in October 2022. The tobacco seedling raising effect shows that the leaves are plump and broad, and the roots and stems are thick; the yield of water spinach covered and planted in the test and demonstration base of Hunan Bangbo Science and Technology Park using the greenhouse film prepared in Example 5 has increased by 21.6%. The greenhouse film prepared in Example 5 has been determined by expert evaluation to be a special film for seedling raising and green leafy vegetables.

[0145] Comparative Example 1

[0146] The inner-added polyolefin seven-layer co-extruded light conversion, high heat preservation, anti-pesticide, long-lasting dripping and anti-fogging greenhouse film described in Comparative Example 1 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2 and an inner layer 1; among them, the outer layer 1 is an anti-aging layer. By mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 90%, acid-resistant anti-aging masterbatch 10%; the outer layer 2 is a light conversion anti-aging layer. By mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 21%, linear low-density polyethylene (LLDPE) 15%, metallocene linear low-density polyethylene (mLLDPE) 45%, acid-resistant anti-aging masterbatch 8%, light conversion masterbatch 11%; the outer layer 3 is a barrier heat preservation, acid-resistant and anti-aging layer. By mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 15%, metallocene linear low-density polyethylene (mLLDPE) 63%, acid-resistant anti-aging masterbatch 10%, heat preservation masterbatch 12%; the middle layer is a high heat preservation, acid-resistant dripping agent reserve layer. By mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 62%, acid-resistant anti-aging masterbatch 8%, dripping agent masterbatch 20%, heat preservation masterbatch 10%; the inner layer 3 is a high heat preservation, acid-resistant dripping agent reserve layer. By mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 65%, acid-resistant anti-aging masterbatch 9%, dripping agent masterbatch 17%, heat preservation masterbatch 9%; the inner layer 2 is a high heat preservation, acid-resistant dripping and anti-fogging agent slow release layer. By mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 67.5%, acid-resistant anti-aging masterbatch 10%, dripping agent masterbatch 15%, anti-fogging masterbatch 1.5%, heat preservation masterbatch 6%; the inner layer 1 is an acid-resistant dripping and anti-fogging agent release layer. By mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 78%, acid-resistant anti-aging masterbatch 9%, dripping agent masterbatch 12%, anti-fogging masterbatch 1%.

[0147] Among the raw materials of the outer layer 1: metallocene linear low-density polyethylene (m-LLDPE), the melt index (MI) is 1.0 g / 10 min, the grade is 2010MA, manufactured by ExxonMobil; acid-resistant anti-aging masterbatch (self-made).

[0148] The raw material composition and preparation method of the acid-resistant anti-aging masterbatch in the raw materials of the outer layer 1 are exactly the same as those of the outer layer 1 in Example 1.

[0149] Among the raw materials of the outer two layers: low-density polyethylene (LDPE) with a melt index (MI) of 0.25 g / 10 min, brand 2420D, manufactured by Daqing Petrochemical; linear low-density polyethylene (LLDPE), with a melt index (MI) of 0.85 g / 10 min, brand 9085, manufactured by Tianjin Union Carbide; metallocene linear low-density polyethylene (m-LLDPE), with a melt index (MI) of 1.0 g / 10 min, brand 1018MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made), and light-conversion masterbatch (self-made).

[0150] The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer 1 in Example 1.

[0151] The raw material composition and preparation method of the light conversion masterbatch are exactly the same as those of the outer two layers in Example 1.

[0152] The raw material composition and raw material brand of the outer 3 layers, the middle layer, the inner 3 layers, the inner 2 layers and the inner 1 layer are exactly the same as those in Example 1.

[0153] The process parameters of the preparation process of this comparative example 1 are exactly the same as those of Example 1, and will not be described again. The specifications of the prepared product are 12000 / 0.12mm, the light transmittance is 89.7%, and the haze is 15.7%.

[0154] The difference between Comparative Example 1 and Example 1 is that no dust-proof masterbatch is added to the outer layer 1, and the greenhouse film does not have a dust-proof function. Dust is adsorbed on the surface of the greenhouse film, and it is not clean even when washed by rain and snow, and microbial plaque is produced, which directly affects the light transmittance and significantly reduces the light conversion efficiency. Other high thermal insulation, pesticide resistance, and drip and defogging properties are comparable.

[0155] The initial light transmittance of the greenhouse film prepared in this comparative example 1 is 89.7%, and the haze is 15.7%. In October 2022, the greenhouse films prepared in this comparative example 1 and Example 1 were subjected to a spliced greenhouse control field application test at the Shandong Agricultural University Experimental Base in Lujiazhuang, Fangxia Town, Laiwu. The yield of sweet peppers planted in March 2023 was 5.75% lower than that of Example 1, and the picking period was delayed by 3 days; the yield of the second crop of kidney beans was 7.36% lower than that of Example 1.

[0156] Comparative Example 2

[0157] The internally added polyolefin seven-layer co-extruded dust-proof, highly heat-insulating, pesticide-resistant, long-lasting anti-dripping and anti-fogging greenhouse film described in Comparative Example 2 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1. Among them, the outer layer 1 is a dust-proof and anti-aging layer. In terms of mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 82%, acid-resistant and anti-aging masterbatch 9%, and dust-proof masterbatch 9%. The outer layer 2 is an anti-aging layer. In terms of mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 23%, linear low-density polyethylene (LLDPE) 17%, metallocene linear low-density polyethylene (mLLDPE) 50%, and acid-resistant and anti-aging masterbatch 10%. The outer layer 3 is a barrier, heat-insulating, acid-resistant and anti-aging layer. In terms of mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 20%, metallocene linear low-density polyethylene (mLLDPE) 60%, acid-resistant and anti-aging masterbatch 9%, and heat-insulating masterbatch 11%. The middle layer is a highly heat-insulating, acid-resistant anti-dripping agent reserve layer. In terms of mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 62%, acid-resistant and anti-aging masterbatch 9%, anti-dripping masterbatch 20%, and heat-insulating masterbatch 9%. The inner layer 3 is a highly heat-insulating, acid-resistant anti-dripping agent reserve layer. In terms of mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 66%, acid-resistant and anti-aging masterbatch 8%, anti-dripping masterbatch 17%, and heat-insulating masterbatch 9%. The inner layer 2 is a highly heat-insulating, acid-resistant anti-dripping and anti-fogging agent slow-release layer. In terms of mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 68.5%, acid-resistant and anti-aging masterbatch 9%, anti-dripping masterbatch 14%, anti-fogging masterbatch 1.5%, and heat-insulating masterbatch 7%. The inner layer 1 is an acid-resistant anti-dripping and anti-fogging agent release layer. In terms of mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 79%, acid-resistant and anti-aging masterbatch 9%, anti-dripping masterbatch 11%, and anti-fogging masterbatch 1%.

[0158] Among the raw materials of the outer layer 1: Metallocene linear low-density polyethylene (m-LLDPE) has a melt index (MI) of 1.0 g / 10 min, grade 2010MA, manufactured by ExxonMobil; acid-resistant and anti-aging masterbatch (self-made); the dust-proof masterbatch has a grade of EFT997 and is manufactured by Tianjin Riken Co., Ltd.

[0159] The raw material composition and preparation process method of the acid-resistant and anti-aging masterbatch are exactly the same as those of the outer layer 1 in Example 2.

[0160] Among the raw materials of the outer 2 layers: the melt index (MI) of low-density polyethylene (LDPE) is 0.25 g / 10 min, grade 2420D, manufactured by Daqing Petrochemical; linear low-density polyethylene (LLDPE), the melt index (MI) is 0.85 g / 10 min, grade 9085, manufactured by Tianjin Lianhua; metallocene linear low-density polyethylene (m-LLDPE), the melt index (MI) is 1.0 g / 10 min, grade 1018MA, manufactured by ExxonMobil; acid-resistant and aging-resistant masterbatch (self-made); the raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer 1 layer in Example 2.

[0161] The raw material composition and grades in the outer 3 layers, middle layer, inner 3 layers, inner 2 layers, and inner 1 layer are exactly the same as those in Example 2.

[0162] The raw material composition and preparation method of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer 1 layer in Example 2.

[0163] The preparation method and process conditions of the internally added polyolefin seven-layer co-extruded dust-proof, high-insulation, anti-pesticide, long-lasting dripping and fog-eliminating greenhouse film described in Comparative Example 2 are exactly the same as those in Example 1. The product specifications obtained are 12000 / 0.12 mm; the light transmittance is 90.2%, the haze is 15.2%, and the designed service life is 2 years.

[0164] The difference between Comparative Example 2 and Example 2 is that no light conversion masterbatch is added and it does not have the light conversion function, and the light intensity in the greenhouse is significantly reduced. Comparative Example 2 and Example 2 were made into a spliced greenhouse and applied and demonstrated in the large field of the experimental base of Shandong Agricultural University in Gaozhuang, Fangxia Town, Laiwu in October 2022. The strawberries (Tianbao) planted had a yield reduction of 20.7% compared to Example 2, and the picking period was postponed by 5 days, with an obvious gap.

[0165] Comparative Example 3

[0166] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, highly heat-insulating, pesticide-resistant, long-acting anti-dripping and anti-fogging greenhouse film described in Comparative Example 3 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1. Among them, the outer layer 1 is a dust-proof and anti-aging layer. Calculated by mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 83%, acid-resistant and anti-aging masterbatch 9%, and dust-proof masterbatch 8%. The outer layer 2 is a light conversion and anti-aging layer. Calculated by mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 25%, linear low-density polyethylene (LLDPE) 15%, metallocene linear low-density polyethylene (mLLDPE) 42%, acid-resistant and anti-aging masterbatch 9%, and light conversion masterbatch 9%. The outer layer 3 is an acid-resistant and anti-aging layer. Calculated by mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 22%, linear low-density polyethylene (LLDPE) 30%, metallocene linear low-density polyethylene (mLLDPE) 40%, and acid-resistant and anti-aging masterbatch 8%. The middle layer is a highly heat-insulating, acid-resistant and anti-dripping agent reserve layer. Calculated by mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 60%, acid-resistant and anti-aging masterbatch 10%, anti-dripping masterbatch 20%, and heat-insulating masterbatch 10%. The inner layer 3 is a highly heat-insulating, acid-resistant and anti-dripping agent reserve layer. Calculated by mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 63%, acid-resistant and anti-aging masterbatch 9%, anti-dripping masterbatch 18%, and heat-insulating masterbatch 10%. The inner layer 2 is a highly heat-insulating, acid-resistant, anti-dripping and anti-fogging agent slow-release layer. Calculated by mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 69.5%, acid-resistant and anti-aging masterbatch 8%, anti-dripping masterbatch 15%, anti-fogging masterbatch 1.5%, and heat-insulating masterbatch 6%. The inner layer 1 is an acid-resistant, anti-dripping and anti-fogging agent release layer. Calculated by mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 80%, acid-resistant and anti-aging masterbatch 8%, anti-dripping masterbatch 11%, and anti-fogging masterbatch 1%.

[0167] The raw material compositions and grades in the outer layer 1 and the outer layer 2 are exactly the same as those in the outer layer 1 and the outer layer 2 of Example 3. The raw material composition and preparation method of the acid-resistant and anti-aging masterbatch are exactly the same as those of the outer layer 1 in Example 3. The raw material composition and preparation method of the light conversion masterbatch are exactly the same as those of the outer layer 2 in Example 3.

[0168] Among the outer three-layer raw materials: the melt index (MI) of low-density polyethylene (LDPE) is 0.25 g / 10 min, and the grade is 2420D, manufactured by Daqing Petrochemical; linear low-density polyethylene (LLDPE), the melt index (MI) is 0.85 g / 10 min, and the grade is 9085, produced by Tianjin Lianhua; metallocene linear low-density polyethylene (m-LLDPE), the melt index (MI) is 1.0 g / 10 min, and the grade is 1018MA, manufactured by ExxonMobil. The raw material composition and preparation method of the acid and aging resistant masterbatch in the outer three layers are exactly the same as those of the outer one layer in Example 3.

[0169] For the outer three layers of this Comparative Example 3, no drip agent guiding inner layer precipitation design scheme barrier layer was made, that is, no metallocene resin with a higher density was used and no hydrotalcite heat preservation masterbatch was added. Therefore, it cannot block the outward migration and precipitation of the drip agent.

[0170] The raw material composition and grades in the middle layer, inner three layers, inner two layers, and inner one layer are exactly the same as those of the middle layer, inner three layers, inner two layers, and inner one layer in Example 3.

[0171] The internally added polyolefin seven-layer coextruded light conversion, dust-proof, high-insulation, anti-pesticide, long-lasting drip and fog-eliminating greenhouse film prepared in this Comparative Example 3 has a product specification of 12000 / 0.12 mm; the designed service life is 2 years. The light transmittance is 90.1%, and the haze is 15.9%; through the greenhouse verification, the duration of the drip and fog-eliminating function is 12 months.

[0172] The difference between the greenhouse film prepared in this Comparative Example 3 and the greenhouse film in Example 3 is that in the outer three layers of this Comparative Example 3, no drip agent guiding inner layer precipitation design scheme was made, that is, no metallocene resin with a higher density was used and no hydrotalcite heat preservation masterbatch was added, which did not play a role in blocking the outward migration of the drip agent. The bidirectional migration of the drip agent caused waste and shortened the durability of the drip function. The drip and fog-eliminating function of the greenhouse film in this Comparative Example 3 failed in October 2023.

[0173] The greenhouse film prepared in this Comparative Example 3 and the greenhouse film in Example 3 were subjected to a splicing greenhouse test. In October 2022, it was demonstrated in the field application of the experimental base of Shandong Agricultural University in Gaozhuang, Fangxia Town, Laiwu. For the tomatoes (Pioneer No. 4) planted, the night temperature in the greenhouse of Comparative Example 3 was 0.5 - 1.0 °C lower than that in Example 3, and the picking was postponed by 3 days.

[0174] Comparative Example 4

[0175] The inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-lasting anti-drip and anti-fog greenhouse film described in Comparative Example 4 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2 and an inner layer 1; among them, the outer layer 1 is a dust-proof and anti-aging layer. In terms of mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 84%, acid-resistant and anti-aging masterbatch 8%, and dust-proof masterbatch 8%; the outer layer 2 is a light conversion and anti-aging layer. In terms of mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 28%, linear low-density polyethylene (LLDPE) 16%, metallocene linear low-density polyethylene (mLLDPE) 35%, acid-resistant and anti-aging masterbatch 11%, and light conversion masterbatch 10%; the outer layer 3 is a barrier, heat-insulating, acid-resistant and anti-aging layer. In terms of mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 18%, metallocene linear low-density polyethylene (mLLDPE) 62%, acid-resistant and anti-aging masterbatch 10%, and heat-insulating masterbatch 10%; the middle layer is an acid-resistant anti-drip agent reserve layer. In terms of mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 70%, acid-resistant and anti-aging masterbatch 9%, and anti-drip masterbatch 21%; the inner layer 3 is an acid-resistant anti-drip agent reserve layer. In terms of mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 76%, acid-resistant and anti-aging masterbatch 8%, and anti-drip masterbatch 16%; the inner layer 2 is an acid-resistant anti-drip and anti-fog agent slow-release layer. In terms of mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 75.5%, acid-resistant and anti-aging masterbatch 9%, anti-drip masterbatch 14%, and anti-fog masterbatch 1.5%; the inner layer 1 is an acid-resistant anti-drip and anti-fog agent release layer. In terms of mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 79%, acid-resistant and anti-aging masterbatch 9%, anti-drip masterbatch 11%, and anti-fog masterbatch 1%.

[0176] The raw material compositions and grades of the outer layer 1, the outer layer 2, and the outer layer 3 are exactly the same as those of the outer layer 1, the outer layer 2, and the outer layer 3 in Example 4; the raw material composition and preparation process method of the acid-resistant and anti-aging masterbatch are exactly the same as those of the outer layer 1 in Example 4; the raw material composition and preparation method of the light conversion masterbatch described in the outer layer 2 are exactly the same as those of the outer layer 2 in Example 4; the raw material composition and preparation method of the heat-insulating masterbatch in the outer layer 3 are exactly the same as those of the outer layer 3 in Example 4.

[0177] The raw material grades of the middle layer, the inner layer 3, the inner layer 2, and the inner layer 1 are exactly the same as those of the middle layer, the inner layer 3, the inner layer 2, and the inner layer 1 in Example 4; the difference is that the hydrotalcite heat-insulating masterbatch in the middle layer, the inner layer 3, and the inner layer 2 of this Comparative Example 4 is replaced by EVA.

[0178] The raw material composition and preparation process of the acid-resistant and aging-resistant masterbatch are exactly the same as those of the outer layer in Example 4; the raw material composition and preparation method of the anti-drip masterbatch are exactly the same as those of the middle layer in Example 1. The raw material composition and preparation method of the anti-fog masterbatch are exactly the same as those of the inner layer 2 in Example 4.

[0179] The preparation method and process conditions of the internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat preservation, anti-pesticide, long-lasting anti-drip and anti-fog greenhouse film described in Comparative Example 4 are exactly the same as those in Example 4.

[0180] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat preservation, anti-pesticide, long-lasting anti-drip and anti-fog greenhouse film prepared in Comparative Example 4 has a product specification of 12000 / 0.12 mm; the designed service life is 2 years. The light transmittance is 90.4%, and the haze is 15.6%. After the greenhouse covering verification, the duration of the anti-drip and anti-fog functions is 17 months. Compared with Example 4, the middle layer, the inner layer 3, and the inner layer 2 in Comparative Example 4 do not add the hydrotalcite heat preservation masterbatch, which reduces the sustained release property of the anti-drip agent and is not conducive to extending the anti-drip lasting performance. The splicing greenhouse of Comparative Example 4 and Example 4 has been applied and demonstrated in the large field of the experimental base of Shandong Agricultural University in Gaozhuang, Fangxia Town, Laiwu in October 2022. The night temperature in the greenhouse is 0.7-1.5 °C lower than that in Example 4, and the picking of the planted blueberries is postponed by 4 days; the anti-drip performance of Comparative Example 4 fails in April 2024, and the anti-drip lasting period is 17 months.

[0181] Comparative Example 5

[0182] The inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-lasting anti-dripping and anti-fogging greenhouse film described in Comparative Example 5 is composed of an outer layer 1, an outer layer 2, an outer layer 3, a middle layer, an inner layer 3, an inner layer 2, and an inner layer 1; among them, the outer layer 1 is a dust-proof and aging-resistant layer. By mass percentage, the outer layer 1 is composed of the following raw materials: metallocene linear low-density polyethylene (mLLDPE) 83%, aging-resistant masterbatch 8%, and dust-proof masterbatch 9%; the outer layer 2 is a light conversion and aging-resistant layer. By mass percentage, the outer layer 2 is composed of the following raw materials: low-density polyethylene (LDPE) 24%, linear low-density polyethylene (LLDPE) 20%, metallocene linear low-density polyethylene (mLLDPE) 35%, aging-resistant masterbatch 10%, and light conversion masterbatch 11%; the outer layer 3 is a barrier, heat-insulating and aging-resistant layer. By mass percentage, the outer layer 3 is composed of the following raw materials: low-density polyethylene (LDPE) 16%, metallocene linear low-density polyethylene (mLLDPE) 63%, aging-resistant masterbatch 9%, and heat-insulating masterbatch 12%; the middle layer is a high heat-insulating anti-dripping agent reserve layer. By mass percentage, the middle layer is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 62%, aging-resistant masterbatch 8%, anti-dripping masterbatch 21%, and heat-insulating masterbatch 9%; the inner layer 3 is a high heat-insulating anti-dripping agent reserve layer. By mass percentage, the inner layer 3 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 65%, aging-resistant masterbatch 9%, anti-dripping masterbatch 17%, and heat-insulating masterbatch 9%; the inner layer 2 is a high heat-insulating anti-dripping and anti-fogging agent slow-release layer. By mass percentage, the inner layer 2 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 68.5%, aging-resistant masterbatch 9%, anti-dripping masterbatch 15%, anti-fogging masterbatch 1.5%, and heat-insulating masterbatch 6%; the inner layer 1 is an anti-dripping and anti-fogging agent release layer. By mass percentage, the inner layer 1 is composed of the following raw materials: ethylene-vinyl acetate copolymer resin (EVA) 79%, aging-resistant masterbatch 9%, anti-dripping masterbatch 11%, and anti-fogging masterbatch 1.0%.

[0183] The raw material compositions and grades in the outer layer 1, the outer layer 2, and the outer layer 3 are exactly the same as those in Example 5. The raw material composition and preparation process method of the acid-resistant and aging-resistant masterbatch in each layer are exactly the same as those of the outer layer 1 in Example 5; the difference between Comparative Example 5 and Example 5 is that the grade of the light stabilizer in the acid-resistant and aging-resistant masterbatch is HALS944, manufactured by BASF Corporation. The preparation method of the light conversion masterbatch is exactly the same as that of the outer layer 2 in Example 5. The raw material composition and preparation method of the heat-insulating masterbatch are exactly the same as those of the outer layer 3 in Example 5.

[0184] The raw material compositions in the middle layer, the inner layer 3, the inner layer 2, and the inner layer 1 are exactly the same as those in Example 5. The difference is that the grade of EVA in the middle layer, the inner layer 3, the inner layer 2, and the inner layer 1 in Comparative Example 5 is FL00012, and the VA content is 12%, produced by Exxon Corporation.

[0185] The preparation method and process conditions of the internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting dripping and anti-fogging greenhouse film described in Comparative Example 5 are exactly the same as those in Example 5.

[0186] The internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting dripping and anti-fogging greenhouse film prepared in Comparative Example 5 has a product specification of 12000 / 0.12mm; the designed service life is 2 years. The light transmittance is 89.9%, the haze is 16.6%, and the duration of the dripping and anti-fogging function is verified to be 15 months after covering the greenhouse. In Comparative Example 5, the design is anti-S ≤ 600PPM; Cl ≤ 100PPM, which is only suitable for covering seedling raising or organic vegetable planting with less pesticide use.

[0187] Compared with Example 5 in Comparative Example 5, the EVA grades in the middle layer, the inner three layers, the inner two layers and the inner one layer are all FL00012, with a VA content of 12%. The storage and slow release properties of the anti-dripping agent in the middle layer, the inner three layers and the inner one layer are not as good as those in Example 5, and the too fast precipitation of the anti-dripping agent is not conducive to extending the dripping persistence performance. In October 2022, Comparative Example 5 and Example 5 were used to make a spliced greenhouse for field application demonstration at the experimental base of Lujiazhuang, Laiwu, Shandong Agricultural University. The dripping performance of Comparative Example 5 failed in January 2024, and the dripping persistence period was 15 months.

[0188] According to the technical requirements of the national standard GB / T20202-2019, the test results of mechanical properties, optical properties, infrared transmittance and dripping performance are shown in Table 2, and the product specification is 12m * 0.10mm.

[0189] Table 2 Test results of various properties of samples

[0190]

[0191] The test results reflected in Table 2 show that the mechanical properties, optical properties and infrared transmittance data of Examples 1-5 and Comparative Examples 1-5 are all better than the index requirements of the national standard, and can meet the most basic requirements for greenhouse covering purposes. The infrared transmittance of Comparative Example 3 without a barrier layer is 69.39% higher than that of Control Example 3; the dripping failure time is reduced by 48%. The infrared transmittance of Comparative Example 4 without using a hydrotalcite heat-insulating masterbatch is 119.2% higher than that of Control Example 4; the dripping failure time is reduced by 30.2%. Comparative Example 5 does not adopt a system for storing and slowly releasing the anti-dripping agent with EVA resin of different VA contents, and the dripping failure time is reduced by 38.5% compared with Control Example 5.

[0192] Table 3 Detection results of the light intensity ratio inside and outside the greenhouse for the light conversion effect

[0193]

[0194] The test data of the light intensity ratio inside and outside the greenhouse with light conversion effect listed in Table 3 were the test results collected on the film of the greenhouse at the agricultural university test base in Fangxia Town, Laiwu City and the demonstration base of Hunan Bangbo Science and Technology Park by using a handheld portable fluorescence spectrometer and an illuminometer. The test data in Table 4 show that the reduction amplitude of the light intensity ratio inside and outside the greenhouse in Examples 1-5 is small with the extension of the greenhouse covering time. After 20 months of greenhouse covering, the light intensity ratio inside and outside the greenhouse remains above 88%, and the light conversion effect is significantly better than that recorded in the prior art, which is above 88% for 8 months. A high light intensity ratio plays a key role in enhancing the photosynthetic efficiency of crops, promoting crop growth, early maturity and increased yield, and improving quality. The light intensity ratio inside and outside the greenhouse tested after 600 days of greenhouse covering decreased by 14.06% for Comparative Example 1 compared with Example 1, 14.56% for Comparative Example 2 compared with Example 2, 3.62% for Comparative Example 3 compared with Example 3, 4.51% for Comparative Example 4 compared with Example 4, and 4.07% for Comparative Example 5 compared with Example 5. It can be seen from this that not adding a dust-proof agent or a light conversion agent has a greater impact on the light intensity ratio inside and outside the greenhouse.

[0195] Table 4 Test Results of Dust-Proof Test

[0196]

[0197]

[0198] In Table 4: a light transmittance ≥ 85% is excellent, 85 > light transmittance ≥ 80% is good, 80 > light transmittance ≥ 75% is average, and light transmittance < 75% is poor. Due to the effect of the dust-proof masterbatch, the surface friction coefficient of the greenhouse film (0.1 ± 0.01) is greatly reduced, and dust and microorganisms are not easily attached to the film surface. After being blown by the wind and rained, it is as bright as new, and the influence on the attenuation rate of the light transmittance is significantly reduced. The annual attenuation rate of Examples 1-5 in this embodiment is below 1.05%. Among them: the annual attenuation rate of the light transmittance of Example 1, Example 3, and Example 4 is 1.0%, and the annual attenuation rate of the light transmittance of Example 2 and Example 5 is 1.05%. Compared with the annual attenuation rate of 1.5% of the existing advanced technology level in the agricultural film industry, it has increased by 30%. A low annual attenuation rate of the light transmittance is a necessary condition for the long-term use of the greenhouse film. Compared with Examples 1-5, the average annual attenuation rate of the light transmittance of Comparative Example 1 is 6.02%, that of Comparative Example 2 is 1.72%, that of Comparative Example 3 is 3.33%, that of Comparative Example 4 is 1.49%, and that of Comparative Example 5 is 1.84%. The relatively large average annual attenuation rate of the light transmittance is caused by not adding a dust-proof agent or not setting a barrier layer to cause the two-way precipitation of the anti-dripping agent.

[0199] The acid and weather resistance of the greenhouse films prepared in Examples 1-5 was tested. The experimental equipment used was a xenon lamp weathering chamber, and the test was carried out in accordance with GB / T 16422.2-2014 Plastics - Methods of exposure to laboratory light sources; Irradiation was carried out according to Method A, with an irradiance of narrowband (340 nm) 0.51 W / (m 2 ·nm), a black standard temperature of 65 °C for the aging test, spraying for 18 min and stopping for 102 min. Once a week during the test period, the specimens were taken out and immersed in a 0.1 mol / L sulfurous acid solution for 24 h. The test samples were respectively clamped on the specimen rack for irradiation and spraying cycles. For greenhouse films with a one-year lifespan, the test was carried out for 1000 hours, and for two-year samples, the test was carried out for 2200 hours to complete the test cycle. The test items were the tensile strength retention rate and the breaking nominal strain retention rate. The technical requirement indicators specified by the standard were: tensile strength retention rate ≥ 60% and breaking nominal strain retention rate ≥ 60%.

[0200] Table 5 Tensile strength test results

[0201]

[0202] Table 6 Tensile strength retention rate test results

[0203] Experiment time / h Measurement result Example 1 Example 2 Example 3 Example 4 Example 5 0 Retention rate of tensile strength / % 100 100 100 100 100 2200 Retention rate of tensile strength / % 65.49 63.92 65.88 64.76 65.96

[0204] Table 7 Elongation at break test results

[0205]

[0206] Table 8 Elongation at break retention rate test results

[0207]

[0208] The above experimental data verified that the anti-aging performance of the greenhouse film samples prepared by the present invention was reliable and fully met the technical requirements specified in GB / T 20202-2019.

Claims

1. An internally added polyolefin seven-layer coextruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-lasting dripping and fog-eliminating greenhouse film, characterized in that: It consists of outer layer 1, outer layer 2, outer layer 3, middle layer, inner layer 3, inner layer 2 and inner layer 1; the outer layer 1 is a dustproof and aging-resistant layer, which is composed of the following raw materials by mass percentage: metallocene linear low-density polyethylene 80%-88%, acid-resistant and aging-resistant masterbatch 5%-10%, and dust-proof masterbatch 7%-10%; the outer layer 2 is a light-converting and aging-resistant layer, which is composed of the following raw materials by mass percentage: low-density polyethylene 20%-30%, linear low-density polyethylene 15 %-25%, metallocene linear low-density polyethylene 35%-45%, light conversion masterbatch 8%-12%, acid and aging resistant masterbatch 5%-10%; the outer three layers are barrier, heat preservation, acid and aging resistant layers. In terms of mass percentage, the outer three layers are composed of the following raw materials: low-density polyethylene 15%-25%, metallocene linear low-density polyethylene 55%-65%, acid and aging resistant masterbatch 5%-10%, and heat preservation masterbatch 10%-15%; the middle layer is a high heat preservation and acid and dripping agent reserve layer, in terms of mass percentage. The middle layer is composed of the following raw materials by mass percentage: 57%-68% ethylene-vinyl acetate copolymer resin, 5%-10% acid-resistant and aging-resistant masterbatch, 15%-25% drip masterbatch, and 8%-12% thermal insulation masterbatch; the inner three layers are high thermal insulation and acid-resistant drip agent reserve layers. By mass percentage, the inner three layers are composed of the following raw materials: 60%-72% ethylene-vinyl acetate copolymer resin, 5%-10% acid-resistant and aging-resistant masterbatch, 15%-18% drip masterbatch, and 8% thermal insulation masterbatch. -12%; the inner 2 layers are high thermal insulation anti-acid dripping and defogging agent sustained-release layers. In terms of mass percentage, the inner 2 layers are composed of the following raw materials: 67%-72% ethylene-vinyl acetate copolymer resin, 5%-10% anti-acid and aging-resistant masterbatch, 12%-15% dripping masterbatch, 1%-3% defogging masterbatch, and 5%-8% thermal insulation masterbatch; the inner 1 layer is the anti-acid dripping and defogging agent release layer. In terms of mass percentage, the inner 1 layer is composed of the following raw materials: 77%-84% ethylene-vinyl acetate copolymer resin, 5%-10% anti-acid and aging-resistant masterbatch, 8%-12% dripping masterbatch, and 1%-3% defogging masterbatch; in: In terms of mass percentage, the acid-resistant and aging-resistant masterbatch is composed of the following raw materials: 45%-53% low-density polyethylene, 30%-40% linear low-density polyethylene, 12%-15% light stabilizer, and 2%-3% antioxidant; Wherein: the melt index of low-density polyethylene is 2.0g / 10min; the melt index of linear low-density polyethylene is 2.0g / 10min; the light stabilizer is a hindered amine acid-resistant light stabilizer, and the hindered amine acid-resistant light stabilizer is at least one of 2011AR, XT-100 or T-69, the manufacturer of 2011AR and XT-100 is BASF, and the manufacturer of T-69 is Beijing Tiangang Company; the antioxidant is a hindered phenol and phosphite composite type, and the antioxidant is any one of B215 or B225; the manufacturer of B215 or B225 is Tianjin Lianlong Company; The melt index of the ethylene-vinyl acetate copolymer resin in the middle layer, inner layer 3, inner layer 2, and inner layer 1 raw materials is 0.25 - 1.0 g / 10 min. Among them, the VA content of the ethylene-vinyl acetate copolymer resin in the middle layer is 19%, the VA content of the ethylene-vinyl acetate copolymer resin in the inner layer 3 is 14%, the VA content of the ethylene-vinyl acetate copolymer resin in the inner layer 2 is 12%, and the VA content of the ethylene-vinyl acetate copolymer resin in the inner layer 1 is 7.5%.

2. The internally added type polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-acting drip and fog elimination greenhouse film according to claim 1, characterized in that: The specific parameters of the raw materials used for the outer layer 3, outer layer 2, and outer layer 1 are as follows: the density of low-density polyethylene is 0.920 - 0.923 g / cm 3 , and the melt index (MI) is 0.2 - 0.75 g / 10 min; The density of linear low density polyethylene is 0.918 - 0.922 g / cm 3 , and the melt index is 0.8 - 1.0 g / 10 min; The density of metallocene linear low density polyethylene is 0.918 - 0.927 g / cm 3 , and the melt index is 0.5 - 1.0 g / 10 min; The dust-proof masterbatch is the dust-proof masterbatch of grade EFT997 produced by Tianjin Riken Co., Ltd. or maleic anhydride grafted type dust-proof masterbatch of grade BE-10F, and the manufacturer is Jilin Bain Plastics Technology Co., Ltd.

3. The inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-lasting anti-dripping and anti-fogging greenhouse film according to claim 1, characterized in that: The preparation method of the acid-resistant and aging-resistant masterbatch is as follows: Add low-density polyethylene, linear low-density polyethylene, light stabilizer, and antioxidant into a kneader according to the proportion for kneading and plasticizing, then feed it into a single-screw extruder granulator through an open mill, and obtain the acid-resistant and aging-resistant masterbatch through hot cutting granulation and air-cooling drying. Among them: the temperature of the kneader is 125 - 140 °C, the plasticizing time is 15 - 20 minutes, and the temperature of the single-screw extruder granulator is 140 - 170 °C.

4. The internally added type polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-acting anti-dripping and anti-fogging greenhouse film according to claim 1, characterized in that: The heat-insulating masterbatch is composed of the following raw materials in mass percentage: 18% - 25% of low-density polyethylene, 15% - 20% of linear low-density polyethylene, 55% - 65% of hydrotalcite heat-insulating agent, 1.0% - 2.0% of coupling agent, 0.5% - 1.5% of lubricant, and 0.5% - 1.5% of dispersant. Among them: the melt index of low-density polyethylene is 2.0 g / 10 min; the melt index of linear low-density polyethylene is 2.0 g / 10 min; the grade of the hydrotalcite heat-insulating agent is HTP, manufactured by Sakai Chemical Co., Ltd., Japan, or any one of the grade HT3 produced by Dandong Xiehe Co., Ltd.; the coupling agent is any one of titanate or aluminate; the lubricant is two or any one of zinc stearate or calcium stearate; the dispersant is polyethylene wax. The preparation method of the heat-insulating masterbatch is as follows: Add low-density polyethylene, linear low-density polyethylene, hydrotalcite heat-insulating agent, coupling agent, lubricant, and dispersant into a kneader according to the proportion for kneading and plasticizing, then feed it into a single-screw extruder granulator through an open mill, and obtain the heat-insulating masterbatch through hot cutting granulation and air-cooling drying. Among them: the temperature of the kneader is 125 - 140 °C, the plasticizing time is 15 - 20 minutes, and the temperature of the single-screw extruder granulator is 140 - 170 °C.

5. The inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-lasting dripping and fog-eliminating greenhouse film according to claim 1, characterized in that: In mass percentage, the light conversion masterbatch is composed of the following raw materials: 36.6% - 49.8% of low-density polyethylene, 38% - 45% of linear low-density polyethylene, 12% - 18% of light conversion agent, and 0.2% - 0.4% of antioxidant. Among them: the melt index of low-density polyethylene is 2.0 g / 10 min; the melt index of linear low-density polyethylene is 2.0 g / 10 min; the light conversion agent is an inorganic rare earth light conversion agent, and the inorganic rare earth light conversion agent is any one or a combination of GTR-650Ⅱ (green to red), GTR-650Ⅲ (green to red), VTB-440 (purple to blue) or VTR660 (purple to red); the antioxidant is a compound of hindered phenols and phosphites, and the antioxidant is any one of B215 or B225; the manufacturer of B215 or B225 is Tianjin Li'anlong Co., Ltd. The preparation method of the light conversion masterbatch is as follows: Add low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), light conversion agent and antioxidant into a kneader according to the proportion for kneading and plasticizing, then feed it into a single-screw extrusion granulator through a two-roll mill, and obtain the light conversion masterbatch through hot cutting granulation and air-cooling drying. Among them: the temperature of the kneader is 125 - 140 °C, the plasticizing time is 15 - 20 minutes, and the temperature of the single-screw extrusion granulator is 140 - 170 °C.

6. The internally added type polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-acting drip and fog-eliminating greenhouse film according to claim 1, characterized in that: By mass percentage, the dripping masterbatch in the middle layer, inner layer 3, inner layer 2, and inner layer 1 raw materials consists of the following raw materials: ethylene-vinyl acetate resin 37% - 42%, linear low-density polyethylene 30.6% - 36.4%, dripping agent 18% - 22%, antioxidant 0.4% - 0.6%, ultrafine silica 5% - 8%. Among them: the melt index of the ethylene-vinyl acetate resin in the dripping masterbatch is 2.0 g / 10 min; the melt index of linear low-density polyethylene is 2.0 g / 10 min; the dripping agent is any one of KF650 or LD777; the antioxidant is any one of B215 or B225, and the manufacturer of B215 or B225 is Tianjin Li'anlong Co., Ltd. The preparation method of the dripping masterbatch is as follows: Add ethylene-vinyl acetate resin, linear low-density polyethylene, dripping agent, antioxidant and ultrafine silica into a high-speed mixer according to the proportion for kneading, and then feed the kneaded material into a twin-screw extrusion granulator, and obtain the dripping masterbatch after strand pelletizing, water cooling, granulation, drying and cooling. Among them: the temperature of the high-speed mixer is 75 - 85 °C, the kneading time is 12 - 15 minutes, and the temperature of the twin-screw extrusion granulator is 150 - 175 °C.

7. The inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-lasting anti-drip and anti-fog greenhouse film according to claim 1, characterized in that: By mass percentage, the anti-fogging masterbatch in the inner layer 2 and inner layer 1 raw materials consists of the following raw materials: ethylene-vinyl acetate resin 45% - 52%, linear low-density polyethylene 35.9% - 43.7%, anti-fogging agent 8% - 12%, antioxidant 0.1% - 0.3%. Among them: the melt index of the ethylene-vinyl acetate resin in the anti-fog masterbatch is 2.0 g / 10 min, the VA content is 14%; the melt index of the linear low-density polyethylene is 2.0 g / 10 min; the anti-fog agent is any one of KF38 or TS403 fluorosurfactants, KF38 is produced by Tianjin Riken Co., Ltd., and TS403 is produced by Dalian Jinlong Chemical Industry; the antioxidant is any one of B215 or B225; the manufacturers of B215 or B225 are both Tianjin Li'anlong Co., Ltd.; The preparation method of the anti-fog masterbatch: the ethylene-vinyl acetate resin, linear low-density polyethylene, anti-fog agent and antioxidant are added to a high-speed mixer according to the proportion for kneading, and then the kneaded material is fed into a twin-screw extruder for granulation. After strand drawing, water cooling, pelletizing, it enters the drying device and is cooled to obtain the anti-fog masterbatch; Among them: the temperature of the high-speed mixer is 75-85 °C, the kneading time is 12-15 minutes, and the temperature of the twin-screw extruder is 150-175 °C.

8. A method for preparing an internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, anti-pesticide, long-acting dripping and anti-fog greenhouse film according to claim 1, characterized in that: The components of the outer 1 layer, outer 2 layer, outer 3 layer, middle layer, inner 3 layer, inner 2 layer and inner 1 layer are respectively mixed and stirred evenly, added to a seven-layer co-extrusion extruder, and after melting, plasticizing, blow molding, cooling and shaping, traction, slitting, edge welding, inkjet marking, and winding, an inner-added polyolefin seven-layer co-extruded light conversion, dust-proof, high-insulation, anti-pesticide, long-lasting dripping and anti-fog greenhouse film is obtained.

9. The preparation method of the internally added polyolefin seven-layer co-extruded light conversion, dust-proof, high heat-insulating, pesticide-resistant, long-lasting dripping and fog-eliminating greenhouse film according to claim 8, characterized in that: In the seven-layer co-extrusion extrusion unit, the temperatures of the outer 1 layer, outer 2 layer, outer 3 layer, middle layer, inner 3 layer, inner 2 layer and inner 1 layer extruders are all 150-200 °C, the die head temperature is 190-210 °C, and the blow-up ratio is 1.5-2.5.

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