Daylighting resin as well as preparation method and application thereof

Abstract

The invention discloses lighting resin as well as a preparation method and application thereof, and belongs to the technical field of lighting type unsaturated polyester resin. Comprising the following components: ethylene glycol, benzoic acid, phthalic anhydride, maleic anhydride, an antioxidant, a defoaming agent, a surfactant, a stabilizer, styrene, a solvent, a first polymerization inhibitor, a second polymerization inhibitor and a third polymerization inhibitor. The alcohol-acid ratio is (1.03-1.13): 1; the molar ratio of unsaturated acid to saturated acid is (2.5-3.5): 1; the mass ratio of benzoic acid to the surfactant is (26.8-44): 1; the preparation method comprises the following steps: 1) reacting ethylene glycol, maleic anhydride, phthalic anhydride, benzoic acid, an antioxidant and a first polymerization inhibitor; the preparation method comprises the following steps of (1) adding a first polymerization inhibitor, (2) heating and preserving heat after the reaction is completed, and (3) cooling, adding a second polymerization inhibitor, cooling, adding a third polymerization inhibitor, a cross-linking agent, a surfactant and a defoaming agent, and adding a solvent to obtain the daylighting resin.According to the preparation method, the surfactant and benzoic acid have a synergistic effect, so that the compatibility of polyester and the cross-linking agent is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of light-gathering unsaturated polyester resin, and particularly relates to a light-gathering resin as well as a preparation method and application thereof. BACKGROUND

[0002] A large amount of symmetrical diols, such as ethylene glycol, is commonly used in the synthesis formula of light-gathering unsaturated polyester resin, which easily causes poor compatibility of the polyester and the crosslinking agent in the resin dilution stage; in the production field of light-gathering resin, the compatibility of the polyester and the crosslinking agent is one of the key factors determining the performance of the product. For a long time, benzoic acid is generally used in the industry to improve the compatibility of the two. However, this traditional method has obvious disadvantages. In the reaction process of the light-gathering resin, benzoic acid will sublimate in the later stage of the reaction due to heating, and a large amount of sublimated benzoic acid vapor is easy to condense in the pipeline, thereby blocking the pipeline system. This not only seriously affects the continuity of production, but also greatly increases the labor cost and equipment loss due to frequent pipeline cleaning and maintenance.

[0003] In Chinese Invention Patent with the title of "Saturated Polyester Resin and Preparation Method Thereof", "Publication No. CN115215970A", the compatibility of the unsaturated polyester and the crosslinking agent is improved by adding isobutyl alcohol in the formula, and the use of benzoic acid is completely abandoned. Isobutyl alcohol can effectively reduce the surface tension between the polyester and the crosslinking agent due to its unique molecular structure, thereby achieving good compatibility effect. However, in actual production, the raw material price of isobutyl alcohol is about 8100 yuan / ton, while the raw material price of national standard benzoic acid is only 7000 yuan / ton, and the price of isobutyl alcohol per ton is 1100 yuan higher than that of benzoic acid. If the conventional addition ratio of isobutyl alcohol and benzoic acid in the production formula of light-gathering resin is calculated, the cost of 33~55 yuan per ton of light-gathering resin produced by using isobutyl alcohol will be increased only in the raw material of the compatibilizer. This does not take into account the additional cost of special protection measures due to the flammable nature of isobutyl alcohol during storage and transportation.

[0004] In the fierce market competition environment, the price sensitivity of light-gathering resin is extremely high, and the downstream application fields such as building light-gathering plate and greenhouse covering material pay great attention to the product price. The cost increase caused by the use of isobutyl alcohol makes the produced light-gathering resin lose the price advantage in the market and greatly reduces the cost performance.

[0005] Therefore, how to effectively control the production cost while ensuring good compatibility of the polyester and the crosslinking agent in the light-gathering resin has become a problem to be solved in the industry. SUMMARY

[0006] The technical problem to be solved by the present application is to overcome the shortcomings of the prior art and provide a light-gathering resin as well as a preparation method and application thereof. The present application improves the compatibility of the polyester and the crosslinking agent through the synergistic effect of the surfactant and benzoic acid.

[0007] In order to achieve the above-mentioned purpose, the present application provides a light collecting resin, comprising the following components in parts by weight: ethylene glycol 20-442 parts, benzoic acid 34-43 parts, phthalic anhydride 102-105 parts, maleic anhydride 240-246 parts, antioxidant 0.4-0.5 parts, first polymerization inhibitor 0.01-0.05 parts, second polymerization inhibitor 0.05-0.08 parts, third polymerization inhibitor 0.01-0.03 parts, defoaming agent 0.97-1.05 parts, surfactant 0.95-1.05 parts, stabilizer 0.01-0.03 parts, crosslinking agent 230-250 parts, solvent 85-125 parts; the molar ratio of alcohol to acid is 1.03-1.13:1, the molar ratio of total alcohol to total acid is referred to as alcohol acid ratio; the molar ratio of unsaturated acid to saturated acid is 2.5-3.5:1; the mass ratio of benzoic acid to surfactant is 26.8-44:1, which improves the comprehensive performance of the resin by optimizing the synergistic effect of the components. The light collecting resin of the present application has good compatibility, low raw material price, and can effectively control the production cost.

[0008] The first polymerization inhibitor, the second polymerization inhibitor, and the third polymerization inhibitor are at least one of methylhydroquinone, hydroquinone, and 4-tert-butylcatechol; the first polymerization inhibitor, the second polymerization inhibitor, and the third polymerization inhibitor are the same or different, the first polymerization inhibitor is added in the pre-polymerization and temperature rising stage, which needs to play an initial inhibition effect at medium-high temperature to prevent the reaction from running out of control too early; the second polymerization inhibitor further blocks the residual free radical activity at the initial stage of cooling to prevent side reactions. The third polymerization inhibitor stabilizes the system at low temperature to avoid slow self-polymerization during storage or subsequent processing.

[0009] The weight ratio of the first polymerization inhibitor, the second polymerization inhibitor, and the third polymerization inhibitor is 1:1-8:0.2-2. This ratio allows the three polymerization inhibitors to synergistically act in their respective temperature intervals, meeting the polymerization inhibition requirements throughout the reaction process. This ratio can regulate the polymerization inhibition intensity at each stage, ensuring that the reaction process is controllable and does not interfere with the final crosslinking and curing, ensuring that the performance of the light collecting resin meets the standards.

[0010] The components further include, by weight, 30.8-31.2 parts of diethylene glycol, 27.8-28.2 parts of propylene glycol, and 12.8-13.2 parts of glycerol. Preferably, 31 parts of diethylene glycol, 28 parts of propylene glycol, and 13 parts of glycerol. The two hydroxyl groups in the diethylene glycol molecule can participate in the esterification reaction of the resin, introducing a flexible ether bond structure. This structure can increase the flexibility of the resin molecular chain, improve the toughness and impact resistance of the resin. The propylene glycol participates in the esterification reaction to control the degree of branching and crosslinking density of the resin, which can balance the rigidity and flexibility of the resin to a certain extent, ensuring that the resin has sufficient mechanical strength and avoiding the brittleness problem caused by excessive rigidity. Glycerol is a trihydric alcohol, and the presence of three hydroxyl groups in the molecule makes it act as a crosslinking point in the reaction, increasing the branching degree and crosslinking density of the resin. This helps to improve the heat resistance, mechanical strength, and weather resistance of the resin.

[0011] The ethylene glycol includes 20-241 parts of crude ethylene glycol with a content of 60%-88% and 0-200 parts of distilled ethylene glycol with a content of 88%-95%. The use of crude ethylene glycol with a content of 60%-88% and distilled ethylene glycol with a content of 88%-95% reduces the cost, and the use of non-standard propylene glycol improves the compatibility.

[0012] The crude ethylene glycol with a content of 60%-88% is purchased from Hebei Fengyi Chemical Product Co., Ltd., and the content is detected using a Shimadzu GC-2014C gas chromatograph at a column temperature of 180°C with a 0.1-microliter sample.

[0013] The antioxidant is at least one of triphenyl phosphite and 2,6-di-tert-butyl-p-methylphenol. As a hindered phenolic antioxidant, 2,6-di-tert-butyl-p-methylphenol can capture free radicals in the oxidation chain reaction, blocking the aging process of the material. Triphenyl phosphite can effectively inhibit oxidative decomposition, prevent material brittleness and transparency loss, and perform excellently especially in high-temperature processing environments.

[0014] The defoaming agent is model UP11; the defoaming agent can inhibit the foam generated by gas release or stirring during the reaction process, avoiding the influence of volume expansion on mass transfer efficiency and equipment operation stability.

[0015] The stabilizer is at least one of 8% copper naphthenate and 5% copper naphthenate; 8% copper naphthenate indicates that the mass percentage of copper content is 8%; 5% copper naphthenate indicates that the mass percentage of copper content is 5%; the stabilizer can inhibit thermal degradation of the resin, preventing molecular chain rupture or color deepening.

[0016] The crosslinking agent is styrene; the crosslinking agent introduces chemical bonds, promotes linear molecular chains to form a three-dimensional network structure, and improves the mechanical strength and solvent resistance of the resin.

[0017] The surface active agent is at least one of a silane coupling agent, a polyether, and a sorbitan fatty acid ester. The silane coupling agent is gamma-methacryloxypropyl trimethoxysilane, abbreviated as KH-570; the polyether is polyethylene glycol 400; and the sorbitan fatty acid ester is sorbitan oleate, abbreviated as Span 80. The surface active agent has the functions of dispersion and wetting, can reduce the interfacial tension between the resin and the solvent, promote the uniform dispersion of the crosslinking agent, the polymerization inhibitor and other components, and avoid the performance unevenness caused by local aggregation.

[0018] The benzoic acid in the application can esterify with the free hydroxyl groups at the ends of the polyester to generate benzoic acid ester bonds, reduces the polarity of the polyester molecules, makes the properties of the polyester and the crosslinking agent more similar, and thus enhances the compatibility of the two; and the surface active agent reduces the interfacial tension between the polyester and the crosslinking agent, weakens the repulsive force between the molecules of the two, and promotes the interaction between the molecules. The surface active agent and the benzoic acid synergistically improve the compatibility of the polyester and the crosslinking agent, make the resin system have stability and uniformity, and avoid the phase separation of the resin.

[0019] The solvent is at least one of dichloroethane and dichloropropane. The solvent dilutes the resin system, reduces the processing viscosity, and facilitates subsequent coating or injection molding.

[0020] The application also provides a preparation method of the light harvesting resin. (1) ethylene glycol, maleic anhydride, phthalic anhydride, benzoic acid, an antioxidant and a first polymerization inhibitor are added into a reaction container, the temperature is raised, and pre-polymerization is performed for 0.5-2 hours; (2) after the pre-polymerization is completed, the temperature is raised to 200-204 DEG C, and the temperature is kept until the acid value is 28.2-32.6 mg / KOH and the cone and plate viscosity is 490.0-528.9 mPa·s; (3) the temperature is lowered, a second polymerization inhibitor is added, the temperature is continuously lowered, a third polymerization inhibitor, a crosslinking agent, a surface active agent, a stabilizer and a defoaming agent are added and uniformly mixed, the temperature is again lowered, and a solvent is added and uniformly mixed; and the light harvesting resin is obtained.

[0021] The specific operation of step (1) is that ethylene glycol, maleic anhydride, phthalic anhydride, benzoic acid, an antioxidant and a first polymerization inhibitor are added into a reaction container, the temperature is raised to 160-165 DEG C, water is discharged after reaction, and then pre-polymerization is performed for 0.5-2 hours; and step (1) is performed under nitrogen protection, the nitrogen protection is achieved by physically isolating oxygen, assisting dehydration and stabilizing the reaction system, and ensures the integrity of the molecular chain of the unsaturated polyester resin, the color stability and the process safety.

[0022] When the formula contains diethylene glycol, propylene glycol, glycerol, the specific operation of step (1) is to add diethylene glycol, propylene glycol, glycerol, ethylene glycol, maleic anhydride, phthalic anhydride, benzoic acid, antioxidant and the first polymerization inhibitor into the reaction container, and after the water is removed by heating to 160-165℃, the prepolymerization reaction is carried out for 0.5-2h.

[0023] The rate of temperature rise in step (2) is 10-15℃ / h, and exceeding this range may cause local overheating or uneven mass transfer; avoiding too fast temperature rise to cause monomer premature consumption or local concentration unevenness, affecting the degree of polycondensation and molecular weight distribution; through controllable temperature rise to ensure that the esterification reaction of carboxylic acid and hydroxyl group is fully carried out, and too fast temperature rise may inhibit the removal efficiency of carboxylic acid; the target of cone and plate viscosity is 480-530mPa•s, and too slow temperature rise will cause the reaction time to be prolonged, the viscosity to exceed the upper limit, and too fast temperature rise will cause local violent polymerization, uneven or excessive viscosity.

[0024] The specific operation of step (3) is to add the second polymerization inhibitor by cooling to 188-193℃, and then add the third polymerization inhibitor, crosslinking agent, surfactant, stabilizer and defoaming agent by further cooling to 150-170℃; then add the solvent by further cooling to 60-70℃; and then cool to ≤50℃; to obtain the daylighting resin.

[0025] According to another aspect of the present application, the above-mentioned daylighting resin or the daylighting resin prepared according to the above-mentioned preparation method is also provided for use in the field of daylighting tiles.

[0026] Compared with the prior art, the present application has the beneficial effects that: 1. The surfactant in the present application synergistically enhances the compatibility of the polyester and the crosslinking agent, improves the stability and uniformity of the resin system, and avoids the phase separation phenomenon of the resin. The benzoic acid can esterify with the free hydroxyl group at the end of the polyester to form a benzoic acid ester bond, which reduces the polarity of the polyester molecules, makes the properties of the polyester and the crosslinking agent more similar, and thus enhances the compatibility of the two; and the surfactant reduces the interfacial tension between the polyester and the crosslinking agent, weakens the repulsive force between the molecules, and promotes the interaction between the molecules.

[0027] 2. The production cost of the present application is low, the process flow is simple and clear, the required raw materials are easy to obtain, the production cost can be effectively controlled, and the present application has economic feasibility and technical operability. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The figure is the daylighting resin prepared in the present application after being frozen at-40℃ for 48h.

[0029] Figure 2 The figure is the daylighting resin prepared in the present application after being frozen at-20℃ for 24h with different contents of surfactant. DETAILED DESCRIPTION

[0030] The application will be further described below with reference to the accompanying drawings. Figures 1-2 The application will be further described below with reference to the accompanying drawings.

[0031] Embodiment 1 is the best embodiment of the application, and the application will be further described below with reference to specific embodiments and comparative examples.

[0032] Activity = moles of unsaturated acid / moles of total saturated acid; Actual consumption = total amount of raw materials / total actual yield; Theoretical consumption = total amount of raw materials / (total amount of raw materials - theoretical water output).

[0033] The chemical additives used in the embodiments and comparative examples of the application are all commercially available, and the specific information is as follows: Diethylene glycol: purchased from Ningbo Hongyixin Import and Export Co., Ltd.; Non-standard propylene glycol: purchased from Hainan Hongfeier Energy Co., Ltd.; Glycerol, also known as glycerin: purchased from Shandong Jiangze International Trade Co., Ltd.; Crude ethylene glycol with a content of 60% to 88%: purchased from Hebei Fengyi Chemical Products Co., Ltd.; Distilled ethylene glycol with a content of 88% to 95%: purchased from Mayton Science & Energy Co., Ltd. Cangzhou Chemical Products Co., Ltd.; Benzoic acid: purchased from Changzhou Tenghui Chemical Co., Ltd.; Phthalic anhydride, referred to as phthalic anhydride: purchased from Zibo Yexing Business Co., Ltd.; Maleic anhydride: purchased from Tianjin Dajia Chemical Co., Ltd.; Triphenyl phosphite: purchased from Jiangsu Changqing Tree New Material Technology Co., Ltd.; 2,6-Di-tert-butyl-4-methyl phenol, referred to as BHT: purchased from Changzhou Yurong Chemical Co., Ltd.; Methylhydroquinone: purchased from Changzhou Yurong Chemical Co., Ltd.; p-Benzenediol: purchased from Changzhou Yurong Chemical Co., Ltd.; 4-tert-Butylcatechol: purchased from Changzhou Yurong Chemical Co., Ltd.; KH-570: purchased from Quanzhou Kangjin New Material Technology Co., Ltd.; Polyethylene glycol 400: purchased from Wuxi Yatai United Chemical Co., Ltd.; Span 80: purchased from Hefei Qiansheng Biological Technology Co., Ltd.; 8% Copper naphthenate: purchased from Shanghai Taoyuan Cobalt Co., Ltd.; 5% Copper naphthenate: purchased from Shanghai Taoyuan Cobalt Co., Ltd.; The type of defoaming agent is UP11, purchased from Taizhou Tianhe Chemical Co., Ltd. Dichloroethane, purchased from Hubei Chuangze Xi Shangmao Co., Ltd. Dichloropropane is 1,2 dichloropropane: purchased from Huantai Fuzhong Chemical Co., Ltd. Styrene: purchased from Shenyang Jinhua Petrochemical Co., Ltd. Gas chromatograph GC-2014C, purchased from Wuhan Kolin Pufeng Instrument Co., Ltd.

[0034] Example 1 The formula of the light collecting resin of this embodiment is composed of the following components: Maleic anhydride 245 parts, phthalic anhydride 105 parts, benzoic acid 35 parts, 95% distilled ethylene glycol 201 parts, 82% content of crude ethylene glycol 20 parts, non-standard propylene glycol 28 parts, glycerol 13 parts, first polymerization inhibitor hydroquinone 0.01 parts, antioxidant triphenyl phosphite 0.45 parts, second polymerization inhibitor hydroquinone 0.08 parts, crosslinking agent styrene 230 parts, third polymerization inhibitor 4-tert-butyl hydroquinone 0.02 parts, surfactant silane coupling agent γ-methacryloyloxy propyl trimethoxysilane 1.01 parts, stabilizer 8% copper naphthenate 0.01 parts, defoaming agent UP11 0.97 parts, solvent dichloroethane 120 parts; The preparation method of this embodiment includes the following steps: (1) Put maleic anhydride, phthalic anhydride, benzoic acid, 95% distilled ethylene glycol, 82% content of crude ethylene glycol, non-standard propylene glycol, glycerol, first polymerization inhibitor hydroquinone and antioxidant triphenyl phosphite into the reaction container, and heat to 160℃ under nitrogen protection after water is discharged, and pre-polymerize for 1h; (2) After the pre-polymerization reaction is completed, heat to 202℃ at a heating rate of 13℃ / h, and keep the temperature until the acid value is 32.6mg / KOH and the cone and plate viscosity is 490mPa•s; (3) Cool to 190℃ and add the second polymerization inhibitor hydroquinone, continue to cool to 160℃ and add the third polymerization inhibitor 4-tert-butyl hydroquinone, crosslinking agent styrene, surfactant γ-methacryloyloxy propyl trimethoxysilane, stabilizer 8% copper naphthenate, and defoaming agent propylene glycol fatty acid ester, and mix well; (4) Cool to 68℃ and add the solvent dichloroethane and mix well; cool to ≤50℃; and obtain the light collecting resin.

[0035] Example 2 The formula of the light collecting resin of this embodiment is composed of the following components: Maleic anhydride 245 parts, phthalic anhydride 105 parts, benzoic acid 43 parts, 95% distilled ethylene glycol 181 parts, 86% content of crude ethylene glycol 45 parts, non-standard propylene glycol 28 parts, glycerol 13 parts, the first polymerization inhibitor hydroquinone 0.05 parts, antioxidant 2, 6-di-tert-butyl-p-methyl phenol 0.45 parts, the second polymerization inhibitor hydroquinone 0.05 parts, crosslinking agent styrene 250 parts, the third polymerization inhibitor methylhydroquinone 0.02 parts, surfactant 1.03 parts, surfactant is composed of polyethylene glycol fatty acid ester and silane coupling agent γ-methacryloyloxy propyl trimethoxysilane in a weight ratio of 1:1, stabilizer 8% copper naphthenate 0.01 parts, the type of defoamer UP11 1 parts, solvent dichloropropane 85 parts; The preparation method of the embodiment comprises the following steps: (1) Put maleic anhydride, phthalic anhydride, benzoic acid, 95% distilled ethylene glycol, 86% content of crude ethylene glycol, non-standard propylene glycol, glycerol, the first polymerization inhibitor hydroquinone and antioxidant 2, 6-di-tert-butyl-4-methyl phenol into a reaction container, and heat to 165℃ under nitrogen protection, and after water is discharged, pre-polymerization is carried out for 2h; (2) After the pre-polymerization is completed, heat to 203℃ at a heating rate of 12℃ / h, and keep the temperature until the acid value is 31.1mg / KOH and the cone and plate viscosity is 528.9mPa·s; (3) Cool to 192℃ and add the second polymerization inhibitor hydroquinone, continue to cool to 150℃ and add the third polymerization inhibitor methylhydroquinone, surfactant, stabilizer 8% copper naphthenate, defoamer polydimethylsiloxane and crosslinking agent styrene, and mix uniformly; (4) Continue to cool to 70℃ and add solvent dichloropropane, and cool to ≤50℃ to obtain the daylighting resin.

[0036] Example 3 The formula of the daylighting resin of the embodiment is composed of the following components: Maleic anhydride 240 parts, phthalic anhydride 103 parts, benzoic acid 43 parts, distilled ethylene glycol 182 parts, 82% content of crude ethylene glycol 36 parts, non-standard propylene glycol 28 parts, glycerol 13 parts, the first polymerization inhibitor hydroquinone 0.05 parts, antioxidant triphenyl phosphite 0.45 parts, the second polymerization inhibitor 8% copper naphthenate 0.07 parts, crosslinking agent styrene 230 parts, the third polymerization inhibitor hydroquinone 0.02 parts, surfactant is silane coupling agent γ-methacryloyloxy propyl trimethoxysilane 0.97 parts, stabilizer 5% copper naphthenate 0.01 parts, the type of defoamer UP11 1.05 parts, solvent dichloropropane 125 parts; The preparation method of the embodiment comprises the following steps: (1) Maleic anhydride, phthalic anhydride, benzoic acid, distilled ethylene glycol, 82% content of crude ethylene glycol, non-standard propylene glycol, glycerol, first polymerization inhibitor hydroquinone and antioxidant triphenyl phosphite are added into the reaction vessel, and heated to 161℃ under nitrogen protection. After water is discharged, pre-polymerization reaction is carried out for 1.5h; (2) After the pre-polymerization reaction is completed, the temperature is raised to 203℃ at a rate of 10℃ / h, and the temperature is kept until the acid value is 30.8mg / KOH and the cone-plate viscosity is 510.7mPa•s; (3) The temperature is lowered to 188℃, and the second polymerization inhibitor 8% naphthenic acid copper is added. The temperature is continuously lowered to 160℃, and the third polymerization inhibitor hydroquinone, the surfactant γ-methacryloxypropyl trimethoxysilane, the stabilizer 5% naphthenic acid copper, the defoaming agent polydimethylsiloxane and the crosslinking agent styrene are uniformly mixed; (4) The temperature is continuously lowered to 65℃, and the solvent dichloropropane is added. After stirring uniformly, dichloropropane is added again. The temperature is lowered to ≤50℃, and the daylighting resin is obtained.

[0037] Example 4 The formula of the daylighting resin of the present example is composed of the following components: Maleic anhydride 245 parts, phthalic anhydride 105 parts, benzoic acid 35 parts, distilled ethylene glycol 182 parts, 88% content of crude ethylene glycol 46 parts, non-standard propylene glycol 28 parts, glycerol 13 parts, first polymerization inhibitor hydroquinone 0.05 parts, antioxidant triphenyl phosphite 0.45 parts, second polymerization inhibitor 4-tert-butyl hydroquinone 0.07 parts, crosslinking agent styrene 231 parts, third polymerization inhibitor hydroquinone 0.03 parts, surfactant 0 parts, stabilizer 5% naphthenic acid copper 0.01 parts, defoaming agent of UP11 type 0.99 parts, solvent dichloroethane 59 parts, solvent dichloropropane 59 parts; The preparation method of the present example comprises the following steps: (1) Maleic anhydride, phthalic anhydride, benzoic acid, distilled ethylene glycol, 88% content of crude ethylene glycol, non-standard propylene glycol, glycerol, first polymerization inhibitor hydroquinone and antioxidant triphenyl phosphite are added into the reaction vessel, and heated to 163℃ under nitrogen protection. After water is discharged, pre-polymerization reaction is carried out for 0.5h; (2) After the pre-polymerization reaction is completed, the temperature is raised to 202℃ at a rate of 13℃ / h, and the temperature is kept until the acid value is 28.2mg / KOH and the cone-plate viscosity is 490.3mPa•s; (3) The temperature is lowered to 193℃, and the second polymerization inhibitor 4-tert-butyl hydroquinone is added. The temperature is continuously lowered to 160℃, and the third polymerization inhibitor 4-tert-butyl hydroquinone, the stabilizer 5% naphthenic acid copper, the defoaming agent polydimethylsiloxane and the crosslinking agent styrene are uniformly mixed; (4) The temperature is continuously lowered to 62℃, and the solvent dichloroethane and dichloropropane are added. After stirring uniformly, the temperature is lowered to ≤50℃, and the daylighting resin is obtained.

[0038] Example 5 The formula of the light harvesting resin of this example consists of the following components: Maleic anhydride 243 parts, phthalic anhydride 104 parts, benzoic acid 35 parts, 86% content of crude ethylene glycol 241 parts, diethylene glycol 31 parts, first polymerization inhibitor hydroquinone 0.05 parts, antioxidant 2, 6-di-tert-butyl-p-methyl phenol 0.45 parts, second polymerization inhibitor hydroquinone 0.07 parts, crosslinking agent styrene 228 parts, third polymerization inhibitor hydroquinone 0.01 parts, surfactant Span 80 0.98 parts, stabilizer 8% copper naphthenate 0.01 parts, defoaming agent UP11 0.98 parts, solvent dichloroethane 117 parts; The preparation method of this example includes the following steps: (1) Put maleic anhydride, phthalic anhydride, benzoic acid, 86% content of crude ethylene glycol, diethylene glycol, first polymerization inhibitor hydroquinone and antioxidant 2, 6-di-tert-butyl-4-methyl phenol into a reaction container, and heat to 161℃ under nitrogen protection, and after water is discharged, pre-polymerize for 1h; (2) After the pre-polymerization reaction is completed, heat to 201℃ at a heating rate of 13℃ / h, and keep the temperature until the acid value is 32.5mg / KOH, and the cone and plate viscosity is 509.4mPa·s; (3) Cool to 188℃, add second polymerization inhibitor hydroquinone, continue to cool to 165℃, add third polymerization inhibitor hydroquinone, surfactant Span 80, stabilizer 8% copper naphthenate, defoaming agent polydimethylsiloxane and crosslinking agent styrene, and mix uniformly; (4) Continue to cool to 60℃, add solvent dichloroethane, stir uniformly, cool to ≤50℃, and obtain the light harvesting resin.

[0039] Example 6 The formula of the light harvesting resin of this example consists of the following components: Maleic anhydride 244 parts, phthalic anhydride 104 parts, benzoic acid 35 parts, distilled ethylene glycol 155 parts, 82% content of crude ethylene glycol 70 parts, non-standard propylene glycol 28 parts, glycerol 13 parts, first polymerization inhibitor hydroquinone 0.05 parts, antioxidant 2, 6-di-tert-butyl-p-methyl phenol 0.45 parts, second polymerization inhibitor hydroquinone 0.07 parts, crosslinking agent styrene 228 parts, third polymerization inhibitor hydroquinone 0.02 parts, surfactant 0.98 parts, surfactant consisting of polyethylene glycol fatty acid ester and silane coupling agent at a weight ratio of 1:1, stabilizer 5% copper naphthenate 0.01 parts, defoaming agent UP11 0.99 parts, solvent dichloroethane 117 parts; The preparation method of this example includes the following steps: (1) Maleic anhydride, phthalic anhydride, benzoic acid, distilled ethylene glycol, 82% content of crude ethylene glycol, non-standard propylene glycol, glycerol, the first polymerization inhibitor hydroquinone and antioxidant 2,6-di-tert-butyl-4-methylphenol are added into a reaction container, and heated to 161℃ under nitrogen protection, and after water is discharged, pre-polymerization reaction is carried out for 1h; (2) After the pre-polymerization reaction is completed, the temperature is increased to 204℃ at a rate of 15℃ / h, and the temperature is kept until the acid value is 28.6mg / KOH, and the cone and plate viscosity is 506.4mPa·s; (3) The temperature is decreased to 190℃, the second polymerization inhibitor hydroquinone is added, and the temperature is continuously decreased to 170℃, the third polymerization inhibitor hydroquinone, the surfactant, the stabilizer 5% copper naphthenate, the defoaming agent propylene glycol fatty acid ester and the crosslinking agent styrene are added and uniformly mixed; (4) The temperature is continuously decreased to 60℃, the solvent dichloroethane is added, and after stirring uniformly, the temperature is decreased to ≤50℃, and the light collecting resin with good compatibility is obtained.

[0040] Table 1 reaction raw materials of examples .

[0041] Comparative example 1 The preparation method of the light collecting resin described in the present comparative example is the same as that of example 1, and the only difference is that in step (1), benzoic acid is not added, and the amount of phthalic anhydride is increased while the activity is ensured to be unchanged, and the amounts of other components are adjusted.

[0042] Comparative example 2 The preparation method of the light collecting resin described in the present comparative example is the same as that of example 2, and the only difference is that in step (1), the amount of benzoic acid is increased, and the amount of phthalic anhydride is correspondingly reduced while the activity is ensured to be unchanged, and the amounts of other components are adjusted.

[0043] Comparative example 3 The preparation method of the light collecting resin described in the present comparative example is the same as that of example 5, and the only difference is that in step (1), the amount of benzoic acid is increased, and the amount of phthalic anhydride is correspondingly reduced while the activity is ensured to be unchanged, and the amounts of other components are adjusted.

[0044] Comparative example 4 The preparation method of the light collecting resin described in the present comparative example is the same as that of example 2, and the only difference is that in step (1), 30 parts of benzoic acid is added, and in step (3), 1.04 parts of surfactant is added, and the surfactant is composed of polyethylene glycol fatty acid ester and silane coupling agent at a weight ratio of 1:1.

[0045] Comparative example 5 The preparation method of a light-collecting resin described in this comparative example is the same as that in Example 3, except that 122 parts of benzoic acid are added in step (1), and 1.04 parts of a surfactant and 0.96 parts of a surfactant silane coupling agent are added in step (3).

[0046] Table 2 Reaction materials of comparative example .

[0047] Performance Testing The performance of the light-collecting resins prepared in the examples and comparative examples was tested. The specific test results are shown in Table 3.

[0048] The tensile strength of the lighting resin is tested in accordance with GB / T2567-2021.

[0049] The tensile elastic modulus of the lighting resin is tested with reference to GB / T2567-2021.

[0050] The elongation at break of the lighting resin is tested in accordance with GB / T2567-2021.

[0051] The bending strength of the lighting resin is tested with reference to GB / T2567-2021.

[0052] The bending elastic modulus of the lighting resin is tested with reference to GB / T2567-2021.

[0053] The impact strength of the lighting resin is tested with reference to GB / T2567-2021.

[0054] The thermal deformation temperature of the lighting resin is tested in accordance with GB / T1643-2019.

[0055] The prepared light-collecting resin was frozen at -40°C for 48 hours, and the color of the light-collecting resin was visually observed; Figure 1 , Figure 1 (a) is a picture of the light-collecting resin prepared in Example 1 after being frozen at -40°C for 48 hours; Figure 1 (b) is a picture of the light-collecting resin prepared in Example 5 after being frozen at -40°C for 48 hours; Figure 1 (c) is a picture of the light-collecting resin prepared in Example 6 after being frozen at -40°C for 48 hours; Figure 1 (d) is a picture of the light-collecting resin prepared in Comparative Example 1 after being frozen at -40°C for 48 hours; Figure 1 (d) is a picture of the light-collecting resin prepared in Comparative Example 2 after being frozen at -40°C for 48 hours.

[0056] Light transmission test method: 50g of the daylighting resin prepared in the examples and comparative examples was added with accelerant and curing agent and stirred rapidly to be uniform, then poured on a plastic film, covered with two layers of daylighting fiberglass felt and a layer of film in turn, and the resin was completely and uniformly infiltrated in the fiberglass felt with a rolling knife, while ensuring the uniformity of the thickness of the plate, then placed in an 80℃ oven for 3min, the plate was taken out and cooled, and the light transmission was observed.

[0057] 50g of the daylighting resin was taken and different contents of surfactant were added, and placed in a refrigerator and frozen at -20℃ for 24h, and the resin layering was observed, see Figure 2 , Figure 2 (a) in the figure is the daylighting resin prepared in Example 4 after adding 0.5% surfactant and freezing at -20℃ for 24h; Figure 2 (b) in the figure is the daylighting resin prepared in Example 4 after adding 0.8% surfactant and freezing at -20℃ for 24h; Figure 2 (c) in the figure is the daylighting resin prepared in Example 4 after adding 1.0% surfactant and freezing at -20℃ for 24h; Figure 2 (d) in the figure is the daylighting resin prepared in Example 4 after adding 1.2% surfactant and freezing at -20℃ for 24h.

[0058] Table 3 Performance test results of examples and comparative examples .

[0059] In the present application, the surfactant and benzoic acid have synergistic effect, which improves the compatibility of the polyester and the crosslinking agent, and makes the resin system have stability and uniformity, avoiding the phase separation of the resin.

[0060] As can be seen from Figure 1 , with the increase of the amount of crude alcohol, the color of the daylighting resin becomes more yellow, and the daylighting resin prepared in Example 5 has a higher color yellow due to the use of a higher amount of crude alcohol. Comparative Example 1 has a clear layered structure, and the compatibility of the polyester and the crosslinking agent is poor due to the absence of benzoic acid and surfactant.

[0061] From the light transmittance test results, it can be seen that the light transmittance of the light collecting resin without benzoic acid is poor, and the results of Example 1 and Comparative Example 2 show that the light transmittance of the light collecting resin does not increase with the increase of the content of benzoic acid, because too much benzoic acid leads to more short-chain molecules in the produced polyester, and more short-chain molecules will cause the tensile properties of the resin to decrease after curing, and also cause the cured plate to become soft. Comparative Example 3 increases benzoic acid and reduces phthalic anhydride, resulting in an increase in short-chain molecules and a decrease in molecular weight of the resin; this reduces the tensile strength and elongation at break, which shows that too much benzoic acid will damage the mechanical properties. From the results of Comparative Example 4 and Comparative Example 5, it can be seen that only when the mass ratio of benzoic acid to surfactant is within the range of the present application can the synergistic effect of the two be achieved, and the comprehensive performance of the resin is improved.

[0062] From the results of the light transmittance test, it can be seen that the light transmittance of the light collecting resin without benzoic acid is poor, and the results of Example 1 and Comparative Example 2 show that the light transmittance of the light collecting resin does not increase with the increase of the content of benzoic acid, because too much benzoic acid leads to more short-chain molecules in the produced polyester, and more short-chain molecules will cause the tensile properties of the resin to decrease after curing, and also cause the cured plate to become soft. Comparative Example 3 increases benzoic acid and reduces phthalic anhydride, resulting in an increase in short-chain molecules and a decrease in molecular weight of the resin; this reduces the tensile strength and elongation at break, which shows that too much benzoic acid will damage the mechanical properties. From the results of Comparative Example 4 and Comparative Example 5, it can be seen that only when the mass ratio of benzoic acid to surfactant is within the range of the present application can the synergistic effect of the two be achieved, and the comprehensive performance of the resin is improved. Figure 2 It can be seen that the addition of 0.5% and 0.8% of the surfactant causes different degrees of stratification after being frozen at -20°C for 24h, and with the increase of the amount of surfactant added, the stratification of the light collecting resin gradually disappears, and considering the cost factor, 1% of the surfactant is selected to improve the compatibility of the crosslinking agent and the polyester, and also to save costs.

[0063] The above description is only a preferred embodiment of the present application, and is not intended to limit the present application in other forms. Any skilled person in the art can modify or change the above disclosed technical content to equivalent embodiments. However, any simple modification, equivalent change and modification made to the above embodiments without departing from the technical solution of the present application, and in accordance with the technical essence of the present application, still falls within the protection scope of the present application.

Claims

1. A lighting resin, characterized in that: The invention comprises the following components in parts by weight: 20-442 parts of ethylene glycol, 34-43 parts of benzoic acid, 102-105 parts of phthalic anhydride, 240-246 parts of maleic anhydride, 0.4-0.5 parts of antioxidant, 0.01-0.05 parts of first polymerization inhibitor, 0.05-0.08 parts of second polymerization inhibitor, 0.01-0.03 parts of third polymerization inhibitor, 0.97-1.05 parts of defoaming agent, 0.95-1.05 parts of surfactant, 0.01-0.03 parts of stabilizer, 230-250 parts of cross-linking agent, and 85-125 parts of solvent; wherein, the molar ratio of total alcohol to total acid is 1.03-1.13:1; the molar ratio of unsaturated acid to saturated acid is 2.5-3.5:1; and the mass ratio of benzoic acid to surfactant is 26.8-44:

1.

2. The light-collecting resin according to claim 1, wherein: The first polymerization inhibitor, the second polymerization inhibitor, and the third polymerization inhibitor are at least one of methylhydroquinone, hydroquinone, and 4-tert-butylcatechol.

3. The light-collecting resin according to claim 1, wherein: The weight ratio of the first polymerization inhibitor, the second polymerization inhibitor and the third polymerization inhibitor is 1:1-8:0.2-2.

4. The light-collecting resin according to claim 1, characterized in that: The invention also includes the following components in parts by weight: 30.8-31.2 parts of diethylene glycol, 27.8-28.2 parts of propylene glycol, and 12.8-13.2 parts of glycerol.

5. The light-collecting resin according to claim 1, characterized in that: The ethylene glycol comprises 20 to 241 parts of crude ethylene glycol with a content of 60% to 88% and 0 to 200 parts of distilled ethylene glycol with a content of 88% to 95%.

6. The method for preparing a lighting resin according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) Add ethylene glycol, maleic anhydride, phthalic anhydride, benzoic acid, antioxidant and first polymerization inhibitor into a reaction vessel, increase the temperature, and perform prepolymerization for 0.5 to 2 hours; (2) After the prepolymerization reaction is completed, the temperature is raised to 200-204°C and maintained until the acid value reaches 28.2-32.6 mg / KOH and the cone-plate viscosity reaches 490.0-528.9 mPa•s; (3) Cooling down and adding the second polymerization inhibitor; continuing to cool down and adding the third polymerization inhibitor, cross-linking agent, surfactant, stabilizer and defoaming agent and mixing; cooling down again and adding the solvent and mixing; obtaining the light-collecting resin.

7. The method for preparing a light-collecting resin according to claim 6, wherein: The specific operation of step (1) is to add ethylene glycol, maleic anhydride, phthalic anhydride, benzoic acid, an antioxidant and a first polymerization inhibitor into a reaction vessel, raise the temperature to 160-165° C. to react and produce water, and then carry out a prepolymerization reaction for 0.5-2 hours.

8. The method for preparing a light-collecting resin according to claim 6, wherein: The heating rate in step (2) is 10-15°C / h.

9. The method for preparing a light-collecting resin according to claim 6, wherein: The specific operation of step (3) is to cool the temperature to 188-193°C, add the second polymerization inhibitor, continue to cool the temperature to 150-170°C, add the third polymerization inhibitor, crosslinking agent, surfactant, stabilizer and defoaming agent and mix them; then cool the temperature to 60-70°C, add the solvent and mix them; cool the temperature to ≤50°C; and obtain the light-collecting resin.

10. Use of the lighting resin according to any one of claims 1 to 5 or the lighting resin prepared by the method according to any one of claims 6 to 9, characterized in that: Application in the field of skylight tiles.

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