Preparation method and application of ultra-soft PVC (polyvinyl chloride) granules

Abstract

The invention discloses a preparation method of ultra-soft PVC (polyvinyl chloride) granules. Comprising the following raw materials in parts by mass: 10-15% of EPVC paste resin, 70-80% of a plasticizer, 5-15% of a multifunctional composite toughening and elasticity-enhancing anti-precipitation agent, 1-3% of a rare earth calcium zinc multifunctional composite heat stabilizer, 0.01-0.02% of a bright release agent, 0.5-1.0% of an antioxidant, 0.1-0.5% of 2-hydroxy-4-n-octyloxydiphenyl, a surface modifier A and a surface modifier B, compared with the prior art, the soft PVC toy granular material has the advantages that the soft PVC toy granular material prepared by the invention has the super-soft characteristic, the skin-like hand feeling and the crystal-like transparent special effect which cannot be achieved by soft PVC, so that the quality of the soft PVC toy granular material has qualitative leap, the domestic blank is filled, and the soft PVC toy granular material is worthy of popularization and application. According to the ultra-soft PVC toy material particles, the material cost of downstream customers is greatly reduced, the complicated batching process and technical difficulty of the downstream customers are reduced, and the product quality and the working efficiency of the downstream customers are improved.

Description

Technical Field

[0001] The invention relates to the field of PVC granular material preparation, in particular to a preparation method of super-soft PVC granular material and application thereof. Background Art

[0002] PVC material is a popular and widely used synthetic material in the world today. Its global usage ranks second among various synthetic materials, and soft PVC has become an important raw material in the toy fishing gear industry due to its advantages such as easy molding, easy coloring, low cost and strong plasticity.

[0003] With the continuous expansion of the application field of soft PVC particles, its development trend has shifted from general use to diversification, specialization and high performance. In recent years, with the continuous improvement of people's living standards, people have more stringent requirements for soft PVC products, which are not only durable, but also beautiful, with high gloss and high transparency on the surface, and good smoothness, flexibility, elasticity and realistic skin effect.

[0004] At present, the hardness of PVC soft PVC particles on the market ranges from 40-80A, and the maximum oil filling ratio is 130%. The hardness of EPVC paste resin paste ranges from 20A-60A, and the maximum oil filling ratio is 300-400%. Super soft and highly transparent PVC particles use EPVC resin powder as the hard segment and plasticizer and softener as the soft segment. The softer the PVC particles, the greater the oil filling ratio and the higher the polymerization degree of EPVC. The larger the molecular weight, the higher the viscosity, the worse the transparency, and the greater the difficulty in the extrusion process, mainly due to:

[0005] 1. The problem of balance in the selection of PVC resin powder;

[0006] The rationality of the selection of PVC resin is very important. Not only the molecular weight should be considered, but also the adverse factors brought about by the viscosity of the resin should be taken into consideration.

[0007] 2. The material has insufficient toughness, elasticity and poor feel;

[0008] 3. Material precipitation and surface stickiness problems;

[0009] 4. Poor transparency;

[0010] 5. The difficulty of mechanical processing: the greater the viscosity of the material, the greater the difficulty and challenge in pelletizing, dehydrating and packaging the material during the extrusion process. Summary of the invention

[0011] The present invention aims to solve the above technical problems and provides a preparation method and application of super soft PVC granules.

[0012] In order to solve the above technical problems, the technical scheme provided by the present invention is: a method for preparing ultra-soft PVC granules, comprising the following raw materials in parts by weight: 10-15% of EPVC paste resin, 70-80% of plasticizer, 5-15% of multifunctional composite toughening and elastic anti-precipitation agent, 1-3% of rare earth calcium zinc multifunctional composite heat stabilizer, 0.01-0.02% of bright release agent, 0.5-1.0% of antioxidant, 0.1-0.5% of 2-hydroxy-4-n-octyloxydiphenylmethane, surface modifier A, surface modifier B;

[0013] The preparation steps are as follows:

[0014] Step 1: Add EPVC paste resin and plasticizer into the reaction emulsification disperser in accordance with the formula ratio, set the oil emulsification temperature to 120°C, and the stirring speed during coagulation to 500-5000r / min;

[0015] Step 2: When the condensation temperature of the reaction emulsifier disperser rises to 80-90°C, add the multifunctional composite toughening and elastic anti-precipitation agent, rare earth calcium zinc multifunctional composite heat stabilizer, bright release agent, antioxidant, and 2-hydroxy-4-n-octyloxybenzophenone successively, and the stirring speed is increased to 8000-12000r / min during condensation;

[0016] Step 3: The temperature in the reaction emulsification disperser rises to 120°C, the emulsification and dispersion is completed, and the mixture is sent to the extrusion equipment by a metering pump;

[0017] Step 4: The reaction emulsified emulsion is extruded through an extruder at a specific temperature and underwater pelletized, and then dehydrated by a dehydration device;

[0018] Step 5: During dehydration, water cooling equipment is used for cooling, wherein the cooling water is water and surface modifier A (water-based emulsified silicone oil mixed in a ratio of 1:20), the water temperature is 5 degrees, and the water content of the dehydrated PVC granules is less than 1%;

[0019] Step 6: The dehydrated ultra-soft PVC particles are dried and anti-sticked by the three-stage fan. After being dried by the first and second stage fans, they enter the third stage fan. The surface modifier B is atomized and sent to the three-stage fan at a ratio of 2% to prevent the ultra-soft PVC particles from sticking.

[0020] Furthermore, the raw materials include the following parts by weight: 10% EPVC paste resin, 75% plasticizer, 10% multifunctional composite toughening and elastic anti-precipitation agent, 2% rare earth calcium zinc multifunctional composite heat stabilizer, 0.02% bright release agent, 0.8% antioxidant, 0.2% 2-hydroxy-4-n-octyloxydiphenylmethane, surface modifier A, and surface modifier B.

[0021] Furthermore, the EPVC paste resin is prepared by blending a P80 paste resin with a polymerization degree and PR-G;

[0022] Among them, the basic composition of PR-G is: calcium carbide, VCM, EDC, degree of polymerization: 1700±100, K value: 77.5-81.0;

[0023] The basic composition of P80 paste resin is calcium carbide, VCM, EDC, K value: 80; degree of polymerization: greater than 2000.

[0024] Furthermore, the plasticizer is one or more of hexamoll dinch, D1050 plasticizer, and ESO.

[0025] Furthermore, the multifunctional composite toughening and elasticity-enhancing anti-precipitation agent includes an emulsion polymer of butadiene and acrylonitrile rubber, 2-chloro-1,3-butadiene, and di(butoxyethoxyethyl) adipate, and the formula ratio is: butadiene and acrylonitrile rubber: emulsion polymer of 2-chloro-1,3-butadiene: di(butoxyethoxyethyl) adipate = 28:5:67;

[0026] The preparation method of the multifunctional composite toughening and elastic anti-precipitation agent is as follows: emulsion polymers of butadiene, acrylonitrile rubber, 2-chloro-1,3-butadiene and di(butoxyethoxyethyl) adipate are added into a reaction emulsification disperser in accordance with the formula ratio, the oil emulsification temperature is set to 70°C, the stirring speed during condensation is 200-300r / min, and the condensation temperature is raised to 65-70°C.

[0027] Furthermore, the antioxidant is composed of [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester and poly(dipropylene glycol) phenyl phosphite, and the formula ratio is 0.5:0.3.

[0028] Furthermore, the surface modifier A is a polysiloxane-polyalkoxy ether copolymer, and the ratio of surface modifier A to water is 1:20; and the surface modifier B is a modified silicone oil with high phenyl functional groups.

[0029] Furthermore, the extrusion equipment is a twin-screw structure, the aspect ratio is required to be 1:60, the screw structure is a full compression section process, the temperature control is divided into three sections, including a high temperature zone, a medium temperature zone and a low temperature zone, the die temperature is 70-90°C, and the pelletizing temperature is 70-90°C;

[0030] Among them, the high temperature area is divided into: Zone 1 240-250℃, Zone 2 230-240℃, Zone 3 220-230℃, Zone 4 210-220℃, Zone 5 200-210℃;

[0031] Medium temperature zone: zone 6 190-200℃, zone 7 170-180℃, zone 8 150-160℃, zone 9 130-140℃, zone 10 120-130℃;

[0032] The low temperature zones are: Zone 11 100-110℃, Zone 12 90-100℃, Zone 13 80-90℃, Zone 14 70-80℃, Zone 15 60-70℃.

[0033] A method for preparing super-soft PVC granules is used for preparing super-soft PVC toy materials.

[0034] The advantages of the present invention over the prior art are as follows: the soft PVC toy granules prepared by the present invention have the characteristics of ultra-softness that soft PVC cannot achieve, skin-like hand feel, and crystal-like transparent special effects, which makes the quality of soft PVC toy materials have a qualitative leap and fills the domestic gap. The ultra-soft PVC toy granules greatly reduce the material cost of downstream customers, reduce the complicated batching process and technical difficulty of downstream customers, and improve the product quality and work efficiency of downstream customers. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is the stress deformation diagram of Example 1 of the present invention.

[0036] Figure 2 It is a stress deformation diagram of Example 2 of the present invention.

[0037] Figure 3 It is the stress deformation diagram of Example 3 of the present invention. DETAILED DESCRIPTION

[0038] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0039] A method for preparing ultra-soft PVC granules, comprising the following raw materials in parts by weight: 10% EPVC paste resin, 77% plasticizer, 10% multifunctional composite toughening and elasticizing anti-precipitation agent, 2% rare earth calcium zinc multifunctional composite heat stabilizer, 0.02% bright release agent, 0.8% antioxidant, 0.2% 2-hydroxy-4-n-octyloxybenzophenone, surface modifier A, and surface modifier B;

[0040] The preparation steps are as follows:

[0041] Step 1: Add EPVC paste resin and plasticizer into the reaction emulsification disperser in accordance with the formula ratio, set the oil emulsification temperature to 120°C, and the stirring speed during coagulation to 500-5000r / min;

[0042] Step 2: When the condensation temperature of the reaction emulsifier disperser rises to 80-90°C, add the multifunctional composite toughening and elastic anti-precipitation agent, rare earth calcium zinc multifunctional composite heat stabilizer, bright release agent, antioxidant, and 2-hydroxy-4-n-octyloxybenzophenone successively, and the stirring speed is increased to 8000-12000r / min during condensation;

[0043] Step 3: The temperature in the reaction emulsification disperser rises to 120°C, the emulsification and dispersion is completed, and the mixture is sent to the extrusion equipment by a metering pump;

[0044] Step 4: The reaction emulsified emulsion is extruded through an extruder at a specific temperature and underwater pelletized, and then dehydrated by a dehydration device;

[0045] Step 5: During dehydration, water cooling equipment is used for cooling, wherein the cooling water is water and surface modifier A (water-based emulsified silicone oil mixed in a ratio of 1:20), the water temperature is 5 degrees, and the water content of the dehydrated PVC granules is less than 1%;

[0046] Step 6: The dehydrated ultra-soft PVC particles are dried and anti-sticked by the three-stage fan. After being dried by the first and second stage fans, they enter the third stage fan. The surface modifier B is atomized and sent to the three-stage fan at a ratio of 2% to prevent the ultra-soft PVC particles from sticking. The particles that have been anti-sticky and dried ensure that the ultra-soft PVC particles will not clump during transportation, and the downstream customers can demould easily during the production process. The product is smooth and feels comfortable.

[0047] Principle of the present invention:

[0048] ①EPVC resin 10-15%

[0049] 1. Use PR-G, specifically Taiwan Formosa Plastics PR-G, whose basic composition is: calcium carbide, VCM, EDC, etc.; low viscosity, good transparency, good flexibility, degree of polymerization: 1700±100K value: 77.5-81.0;

[0050] 2. Polymerization degree P80 paste resin, specifically German Vinnolit PVC paste, P80 is basically composed of calcium carbide, VCM, EDC, etc.; high transparency, high polymerization degree, high brightness K value: 80 Polymerization degree: greater than 2000

[0051] Selecting high polymerization degree P80 paste resin and PRG to blend and increase the molecular weight of the blend is the key point to increase the oil filling ratio of the resin, reduce the hardness, and ensure no precipitation at high oil filling ratio. The ratio of PR-G:P80 in this formula system is 70:30

[0052] ②Plasticizer 70-80%

[0053] 1. Environmentally friendly plasticizer Dinch; is a transparent, colorless, almost odorless plasticizer. Dinch is a polar plasticizer, so in addition to PVC, it is also compatible with many polar rubbers and thermoplastics, such as: chloroprene rubber, NBR nitrile rubber, etc., - [Molecular weight]: 424.657] Flash point: 229.6 ± 20.2 ° C, [Refractive index]: 1.466; It is designed for sensitive applications, can be used in contact applications and has toxicological properties. It can be used in medical devices, toys and food packaging, and is the main plasticizer in this formulation system.

[0054] 2.D1050 plasticizer is Changchun D1050 from Taiwan, China; polyester environmentally friendly plasticizer; its basic composition is adipic acid and polyol-free polyester; molecular weight 2000, flash point 288 (℃): refractive index (25℃): 1.463-1.470; it has good compatibility with PVC, high temperature resistance and good migration resistance, and has good compatibility with PVC, high temperature resistance, migration resistance, and is used in combination with the main plasticizer and auxiliary plasticizer, with complementary performance to achieve a good plasticizing effect. In this formula system, it is used as a secondary plasticizer and a product anti-precipitation agent

[0055] 3. SO is Xinjinlong ESO, E-10 epoxy soybean oil; molecular weight 1000; flash point (open cup method) ℃ ≥ 280; epoxy soybean oil is a widely used environmentally friendly plasticizer and stabilizer, with low volatility, good thermal stability and light stability. It has a high epoxy value, good compatibility with PVC, good plasticizing effect, good insulation, and good environmental stability. In this formula system, it is used as an environmentally friendly auxiliary plasticizer to take into account the thermal stability of the product.

[0056] The ratio of plasticizer in this formula system is DINCH:D1050:ESO; 85%:10%:5%;

[0057] ③Multifunctional composite toughening and elasticity-enhancing anti-precipitation agent 5-15%

[0058] Main Ingredients:

[0059] 1# Butadiene and acrylonitrile rubber, acrylonitrile content is about 26%, molecular weight is 50000-60000;

[0060] 2#2-chloro-1,3-butadiene emulsion polymer, molecular weight 40000-50000, in line with EU REACH, Rohs, Green Partner and other environmental regulations. Domestic,

[0061] 3# Di(butoxyethoxyethyl) adipate, molecular weight 435, refractive index 1.466; it is a highly compatible plasticizer specially used to give various elastomers maximum low-temperature flexibility, and is used as a diluent and compatible plasticizer in this modifier

[0062] The basic formula ratio of the multifunctional composite toughening and elasticity-enhancing anti-precipitation agent is: 1#:2#:3#=28:5:67;

[0063] Firstly, butadiene, acrylonitrile rubber, 2-chloro-1,3-butadiene rubber and di(butoxyethoxyethyl) adipate are added into a reaction emulsifier disperser in accordance with the formula ratio. The oil emulsification temperature is set to 70°C, the stirring speed is 200-300r / min during condensation, and the condensation temperature is raised to 65-70°C. The performance indicators of the obtained product meet the use requirements of the surface modifier product standard.

[0064] The surface modifier in this formula system acts as a toughening, softening and elasticizing agent for ultra-soft PVC. It has excellent complementary effects in terms of toughening and elasticizing properties, and plays a great role in the anti-precipitation performance of ultra-soft PVC. The multi-component blending modification technology has a good synergistic effect.

[0065] ④Rare earth calcium zinc multifunctional composite heat stabilizer 1-3%

[0066] WINNERWWP-G08 rare earth calcium zinc multifunctional heat stabilizer is non-toxic, odorless, green and environmentally friendly, safe and hygienic. It is a high-tech product transformed from the results of the national '863' high-tech research project. It is composed of an appropriate amount of rare earth and / or hydrotalcite, organic functional compounds such as calcium and zinc, combined with internal and external lubricants, high-efficiency synergists, etc. It has good dispersibility and compatibility with PVC, anti-precipitation, excellent thermal stability and excellent initial colorability, good transparency, and bright color of the product; the main heat stabilizer in this formula system takes into account the transparency of the product.

[0067] ⑤ Bright release agent 0.01-0.02%

[0068] Heda incromax 100 mold release agent has a long-lasting lubricating effect. Even when the addition amount is as small as 1000PPM, it can still have a good lubrication and demoulding effect. It has good transparency and high brightness. This formula system is mainly a lubricating mold release agent and takes into account the transparency of the product.

[0069] ⑥(Antioxidants) 0.5-1.0%

[0070] 1. Main antioxidant: 0.5

[0071] Pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, BASF, is a high molecular weight hindered phenol antioxidant, molecular weight 1177.65, transmittance 425nm ≥ 96% 500nm ≥ 98%, this product has low volatility, good extraction resistance, high thermal stability, and long lasting effect

[0072] 2. Auxiliary antioxidant 2103 poly (dipropylene glycol) phenyl phosphite (PDP). 0.3

[0073] 2103, poly (dipropylene glycol) phenyl phosphite (PDP), is an auxiliary antioxidant for organic polymers. Molecular weight 2100, refractive index (25°C), 1.5340-1.5380, in PVC as an auxiliary stabilizer and chelating agent, providing brighter and more lasting color, and can improve the thermal stability of PVC.

[0074] In this formula system: pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and poly(dipropylene glycol) phenyl phosphite (PDP) are used as main and auxiliary antioxidants and work together with antioxidants to act as antioxidants, anti-yellowing agents, anti-aging agents and heat stabilizers.

[0075] ⑦2-Hydroxy-4-octyloxybenzophenone, 0.1-0.5%

[0076] 2-Hydroxy-4-n-octyloxybenzophenone, BASF UV-531 (BP-12), content ≥ 99%; transmittance 450nm> 90% 500nm> 95%. It is an excellent and efficient anti-aging agent with the characteristics of light color, non-toxicity, good compatibility, low migration, and easy processing. It has the greatest protective effect on polymers and helps to reduce color, while delaying yellowing and blocking physical property loss. In this formula system, it works with antioxidants as an anti-yellowing anti-aging agent.

[0077] ⑧Surface modifier A: surface modifier A: water 1:20

[0078] Polysiloxane-polyalkoxy ether copolymer, domestically produced, transparent water-soluble emulsified silicone oil, a special hydrophilic group-modified silicone polymer, has high bond energy, soft molecular chain, and surface tension of silicone polymer compounds. Viscosity (25℃PaS) 500-3500, refractive index (25℃) 1.440-1.450, and is an isolation agent for rubber and plastic products. It has good demulsification properties and gives the product a smooth, bright, soft and comfortable feel. The external water-based emulsified silicone oil in this formula system ensures the anti-stickiness and smoothness of PVC particles in the early pelletizing and dehydration process of the dehydrator. The surface modifiers AB have complementary advantages and are indispensable.

[0079] ⑨Surface modifier B: add 2 kg of surface modifier B to 100 kg of particles

[0080] Modified silicone oil with high phenyl functional group, SIC 64※※, domestic: refractive index / 25℃1.5340±0.0050, viscosity / 25℃CPS800-1400, excellent scratch resistance, dry and slippery feel, high transparency, excellent compatibility, smoothness and demoulding performance. It has both external and internal lubrication functions. External lubrication can improve the processing performance of materials, increase fluidity, and reduce equipment wear. Forming a uniform lubricating layer on the plastic surface can significantly reduce the surface friction coefficient and improve wear resistance; this formula system ensures the anti-adhesion agent during the drying process, packaging and transportation of ultra-soft PVC particles. Release agent in later injection molding products. And give the product a dry and slippery feel.

[0081] The advantages of surface modifiers AB complement each other and neither is indispensable. Specific embodiment:

[0083] Embodiment 1:

[0084] ①EPVC paste resin 10%;

[0085] EPVC paste resin is made by blending P80 paste resin with PR-G, and the ratio of PR-G to P80 paste resin is 70:30.

[0086] ②Plasticizer 77%;

[0087] Environmentally friendly plasticizer hexamoll dinch is the main plasticizer in this formulation system;

[0088] D1050, whose basic composition is adipic acid and polyol-free polyester, molecular weight: 2000, flash point 288 (℃), refractive index (25℃): 1.463-1.470, is used as a secondary plasticizer and an anti-precipitation agent of the product in this formula system;

[0089] ESO, molecular weight 1000, flash point (open cup method) ℃ ≥ 280, is used as an environmentally friendly auxiliary plasticizer in the formulation system while taking into account the thermal stability of the product;

[0090] The ratio of plasticizer in this formula system is DINCH:D1050:ESO; 85%:10%:5%.

[0091] ③Multifunctional composite toughening, elasticity-enhancing and anti-precipitation agent 10%;

[0092] 1# Butadiene and acrylonitrile rubber, acrylonitrile content is about 26%, molecular weight is 50000-60000;

[0093] 2# Emulsion polymer of 2-chloro-1,3-butadiene, molecular weight 40000-50000;

[0094] 3# Di(butoxyethoxyethyl) adipate, molecular weight 435, refractive index 1.466, used as diluent and compatible plasticizer in this modifier;

[0095] The basic formula ratio of the multifunctional composite toughening, elasticity-enhancing and precipitation-proof agent is: 1#:2#:3#;,28:5:67, and the preparation method is as follows: butadiene and acrylonitrile rubber and 2-chloro-1,3-butadiene rubber and di(butoxyethoxyethyl) adipate are added into the reaction emulsifier disperser in sequence according to the formula ratio, the oil emulsification temperature is set to 70°C, the stirring speed during condensation is 200-300r / min, and the condensation temperature is raised to 65-70°C. The various performance indicators of the obtained product meet the use requirements of the surface modifier product standard.

[0096] ④Rare earth calcium zinc multifunctional composite heat stabilizer 2%;

[0097] WINNERWWP-G08 rare earth calcium zinc multifunctional heat stabilizer is composed of appropriate amount of rare earth and / or hydrotalcite, organic functional compounds such as calcium and zinc, and internal and external lubricants, high-efficiency synergists, etc. It has good dispersibility and compatibility with PVC, anti-precipitation, excellent thermal stability and initial colorability, good transparency, and bright color of the product; the main heat stabilizer in this formula system takes into account the transparency of the product.

[0098] ⑤ Bright release agent 0.02%;

[0099] Hoda incromax 100 mold release agent has a long-lasting lubricating effect. Even when the addition amount is as small as 1000PPM, it can still have a good lubrication and demoulding effect. It has good transparency and high brightness. This formula system mainly uses the lubricating mold release agent while taking into account the transparency of the product.

[0100] ⑥ Antioxidant 0.8%;

[0101] 1. Main antioxidant: 0.5

[0102] Tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester is a high molecular weight hindered phenol antioxidant with a molecular weight of 1177.65 and a transmittance of 425nm≥96% and 500nm≥98%. This product has low volatility, good extraction resistance, high thermal stability and long lasting effect.

[0103] 2. Auxiliary antioxidant 2103 poly (dipropylene glycol) phenyl phosphite (PDP), 0.3

[0104] Poly(dipropylene glycol) phenyl phosphite (PDP) is an auxiliary antioxidant for organic polymers. Molecular weight is 2100, refractive index (25°C) is 1.5340-1.5380. It acts as an auxiliary stabilizer and chelating agent in PVC, providing brighter and more durable colors, and improving the thermal stability of PVC.

[0105] In this formula system: pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and poly(dipropylene glycol) phenyl phosphite (PDP) are used as main and auxiliary antioxidants and work together with antioxidants to act as antioxidants, anti-yellowing agents, anti-aging agents and heat stabilizers.

[0106] ⑦2-Hydroxy-4-octyloxybenzophenone 0.2%;

[0107] 2-Hydroxy-4-n-octyloxybenzophenone, content ≥ 99%; light transmittance 450nm> 90%, 500nm> 95%, is an excellent high-efficiency anti-aging agent with the characteristics of light color, non-toxicity, good compatibility, low migration, easy processing, etc. It has the greatest protective effect on polymers and helps to reduce color, while delaying yellowing and blocking physical property loss. In this formula system, it works with antioxidants as an anti-yellowing anti-aging agent.

[0108] ⑧Surface modifier A;

[0109] Polysiloxane-polyalkoxy ether copolymer, transparent water-soluble emulsified silicone oil, a specific hydrophilic group-modified silicone polymer, has high bond energy, soft molecular chain, surface tension, viscosity (25℃PaS) 500-3500, refractive index (25℃) 1.440-1.450, and is a release agent for rubber and plastic products. It has good demulsification properties and gives the product a smooth, bright, soft and comfortable feel. The external water-based emulsified silicone oil in this formula system ensures the anti-stickiness and smoothness of PVC particles in the early pelletizing and dehydration process of the dehydrator.

[0110] ⑨Surface modifier B;

[0111] Modified silicone oil with high phenyl functional group, refractive index / 25℃1.5340±0.0050, viscosity / 25℃CPS800-1400, excellent scratch resistance, dry and slippery feel, high transparency, excellent compatibility, smoothness and demoulding performance. It has both external and internal lubrication functions. External lubrication can improve the processing performance of materials, increase fluidity, and reduce equipment wear. Forming a uniform lubricating layer on the plastic surface can significantly reduce the surface friction coefficient and improve wear resistance; this formula system ensures the anti-adhesion agent during the drying process, packaging and transportation of ultra-soft PVC particles. Release agent in later injection molding products. And give the product a dry and slippery feel.

[0112] The specific preparation method is:

[0113] Step 1: Add EPVC paste resin and plasticizer into the reaction emulsifier disperser in accordance with the formula ratio, set the oil emulsification temperature to 120°C, and the stirring speed during coagulation to 500r / min;

[0114] Step 2: When the condensation temperature of the reaction emulsifier disperser rises to 80°C, add the multifunctional composite toughening and elastic anti-precipitation agent, rare earth calcium zinc multifunctional composite heat stabilizer, bright release agent, antioxidant, and 2-hydroxy-4-n-octyloxybenzophenone successively, and the stirring speed is increased to 8000r / min during condensation;

[0115] Step 3: The temperature in the reaction emulsification disperser rises to 120°C, the emulsification and dispersion is completed, and the mixture is sent to the extrusion equipment by a metering pump;

[0116] Step 4: The reaction emulsified emulsion is extruded through an extruder at a specific temperature and underwater pelletized, and then dehydrated by a dehydration device;

[0117] Step 5: During dehydration, water cooling equipment is used for cooling, wherein the cooling water is water and surface modifier A (water-based emulsified silicone oil mixed in a ratio of 1:20), the water temperature is 5 degrees, and the water content of the dehydrated PVC granules is less than 1%;

[0118] Step 6: The dehydrated ultra-soft PVC particles are dried and anti-sticked by the three-stage fan. After being dried by the first and second stage fans, they enter the third stage fan. The surface modifier B is atomized and sent to the three-stage fan at a ratio of 2% to prevent the ultra-soft PVC particles from sticking.

[0119] Embodiment 2:

[0120] ①EPVC resin 15%

[0121] Choose high polymerization degree P80 paste resin and PRG to blend, the ratio of PR-G:P80 is 90:10;

[0122] ②Plasticizer 72%

[0123] Environmentally friendly plasticizer hexamoll dinch is used as the main plasticizer, D1050 secondary plasticizer is used as the product's anti-precipitation agent, and ESO is used as an environmentally friendly auxiliary plasticizer to take into account the thermal stability of the product. The ratio is DINCH: D1050: ESO; 85%: 10%: 5%;

[0124] ③Multifunctional composite toughening and elastic anti-precipitation agent 10%

[0125] 1# Butadiene and acrylonitrile rubber, acrylonitrile content is about 26%, molecular weight is 50000-60000;

[0126] 2# Emulsion polymer of 2-chloro-1,3-butadiene, molecular weight 40000-50000;

[0127] 3# Di(butoxyethoxyethyl) adipate, molecular weight 435, refractive index 1.466, used as diluent and compatible plasticizer in this modifier;

[0128] The basic formula ratio is: 1#:2#:3#; 28:5:67, and the preparation method is: first, butadiene and acrylonitrile rubber and 2-chloro-1,3-butadiene rubber and di(butoxyethoxyethyl) adipate are added into the reaction emulsification disperser in sequence according to the formula ratio, the oil emulsification temperature is set to 70°C, the stirring speed during condensation is 200-300r / min, and the condensation temperature is raised to 65-70°C. Under the conditions, the various performance indicators of the obtained product meet the use requirements of the surface modifier product standard.

[0129] ④Rare earth calcium zinc multifunctional composite heat stabilizer 2%

[0130] The main heat stabilizer in the formulation system takes into account the transparency of the product.

[0131] ⑤ Bright release agent 0.02%

[0132] This formula system mainly contains lubricating release agent while taking into account the transparency of the product.

[0133] ⑥(Antioxidants) 0.8%

[0134] 1. Primary antioxidant: 0.5, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate;

[0135] 2 Auxiliary antioxidant 2103 poly (dipropylene glycol) phenyl phosphite (PDP). 0.3;

[0136] Pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and poly(dipropylene glycol)phenyl phosphite (PDP) are used as main and auxiliary antioxidants and antioxidants to work together as antioxidants, anti-yellowing agents, anti-aging agents and heat stabilizers.

[0137] ⑦2-Hydroxy-4-octyloxybenzophenone, 0.2%

[0138] In this formula system, it works together with antioxidants as an anti-yellowing and anti-aging agent.

[0139] ⑧Surface modifier A: surface modifier A: water 1:20

[0140] This formula system ensures the anti-stickiness and smoothness of PVC particles during the early pelletizing and dehydration processes of the dehydrator.

[0141] ⑨Surface modifier B: add 2 kg of surface modifier B to 100 kg of particles

[0142] The specific preparation method is:

[0143] Step 1: Add EPVC paste resin and plasticizer into the reaction emulsifier disperser in accordance with the formula ratio, set the oil emulsification temperature to 120°C, and the stirring speed during coagulation to 2000r / min;

[0144] Step 2: When the condensation temperature of the reaction emulsifier disperser rises to 80°C, add the multifunctional composite toughening and elastic anti-precipitation agent, rare earth calcium zinc multifunctional composite heat stabilizer, bright release agent, antioxidant, and 2-hydroxy-4-n-octyloxybenzophenone successively, and the stirring speed is increased to 10000r / min during condensation;

[0145] Step 3: The temperature in the reaction emulsification disperser rises to 120°C, the emulsification and dispersion is completed, and the mixture is sent to the extrusion equipment by a metering pump;

[0146] Step 4: The reaction emulsified emulsion is extruded through an extruder at a specific temperature and underwater pelletized, and then dehydrated by a dehydration device;

[0147] Step 5: During dehydration, water cooling equipment is used for cooling, wherein the cooling water is water and surface modifier A (water-based emulsified silicone oil mixed in a ratio of 1:20), the water temperature is 5 degrees, and the water content of the dehydrated PVC granules is less than 1%;

[0148] Step 6: The dehydrated ultra-soft PVC particles are dried and anti-sticked by the three-stage fan. After being dried by the first and second stage fans, they enter the third stage fan. The surface modifier B is atomized and sent to the three-stage fan at a ratio of 2% to prevent the ultra-soft PVC particles from sticking.

[0149] Embodiment 3:

[0150] ①EPVC resin 20

[0151] 1.PR-G: Its basic composition is calcium carbide, VCM, EDC, etc., low viscosity, good transparency, good flexibility, degree of polymerization: 1700±100, K value: 77.5-81.0;

[0152] The PRG paste resin is selected as the main raw material in the formula system. The polymerization degree and oil filling ratio of the PVC paste resin are considered according to the product hardness standard to ensure no precipitation under high oil filling ratio and the processing performance and fluidity of the product.

[0153] ②Plasticizer 69%

[0154] 1. Bis(2-ethylhexyl)terephthalate, English name: Bis(2-ethylhexyl)terephthalate, molecular weight 390.556, flash point 208.4±8.5℃, refractive index n20 / D 1.4890-1.4910

[0155] Due to its low volatility, high and low temperature resistance, high insulation, anti-migration, anti-extraction, etc., and because DOTP does not contain phthalates, it is not within the scope of the 16 phthalate-containing plasticizers restricted for use in the EU and other countries. Therefore, it is an excellent environmentally friendly plasticizer and the main plasticizer in this formula system.

[0156] 2. Polypropylene adipate environmentally friendly plasticizer W-2500, molecular weight 2500, viscosity 2800, flash point 275 (℃): refractive index (25℃): 1.463-1.470; good compatibility with PVC, good high temperature resistance and migration resistance, good compatibility with PVC, high temperature resistance, migration resistance, mixed with the main plasticizer and auxiliary plasticizer, complementary performance, to achieve a good plasticizing effect. In this formula system, it is used as a secondary plasticizer and a product anti-precipitation agent.

[0157] 3.ESO; E-10 epoxy soybean oil; molecular weight 1000; flash point (open cup method) ℃ ≥ 280; epoxy soybean oil is a widely used environmentally friendly plasticizer and stabilizer, with low volatility, good thermal stability and light stability, high epoxy value, good compatibility with PVC, good plasticizing effect, good insulation, good environmental stability. In this formula system, it is used as an environmentally friendly auxiliary plasticizer to take into account the thermal stability of the product. The ratio of plasticizer in this formula system is DINCH: D1050: ESO; 85%: 10%: 5%;

[0158] ③Surface modifier 8%

[0159] Ethylene-vinyl acetate-carbonyl (E / VA / CO) terpolymer has a molecular weight comparable to that of PVC and good compatibility with PVC. It can replace some low-molecular-weight plasticizers in PVC formulations and can be used on PVC to avoid most of the sequelae. Elvaloy also has excellent low-temperature impact resistance and rubber-like feel, and can achieve the required balance of toughness, transparency, and impact performance. In ultra-soft PVC formulations, it not only has the effect of toughening and softening, but also has a good anti-precipitation effect in the case of high oil filling ratios of PVC. It can also be used as a plasticizer.

[0160] ④Rare earth calcium zinc multifunctional heat stabilizer 2%

[0161] WINNERWWP-G08 rare earth calcium zinc multifunctional heat stabilizer is non-toxic, odorless, green and environmentally friendly, safe and hygienic. It is a high-tech product transformed from the results of the national '863' high-tech research project. It is composed of an appropriate amount of rare earth and / or hydrotalcite, organic functional compounds such as calcium and zinc, combined with internal and external lubricants, high-efficiency synergists, etc. It has good dispersibility and compatibility with PVC, anti-precipitation, excellent thermal stability and excellent initial colorability, good transparency, and bright color of the product; the main heat stabilizer in this formula system takes into account the transparency of the product.

[0162] ⑤ Bright release agent 0.03

[0163] Heda incromax 100 mold release agent has a long-lasting lubricating effect. Even when the addition amount is as small as 1000PPM, it can still have a good lubrication and demoulding effect. It has good transparency and high brightness. This formula system is mainly a lubricating mold release agent and takes into account the transparency of the product.

[0164] ⑥ Antioxidant 0.8%

[0165] 1. Main antioxidant; pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 0.5

[0166] Pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, BASF: Antioxidant 1010 is a high molecular weight hindered phenol antioxidant, molecular weight 1177.65, transmittance 425nm ≥ 96% 500nm ≥ 98%, this product has low volatility, good extraction resistance, high thermal stability and long lasting effect

[0167] 2. Auxiliary antioxidant: poly (dipropylene glycol) phenyl phosphite (PDP), 0.3

[0168] 2103, poly (dipropylene glycol) phenyl phosphite (PDP), is an auxiliary antioxidant for organic polymers. Molecular weight 2100, refractive index (25°C), 1.5340-1.5380, in PVC as an auxiliary stabilizer and chelating agent, providing brighter and more lasting color, and can improve the thermal stability of PVC.

[0169] In this formula system, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate and poly(dipropylene glycol) phenyl phosphite (PDP) are used as main and auxiliary antioxidants and antioxidants to work together as antioxidants, anti-yellowing agents, anti-aging agents and heat stabilizers.

[0170] ⑦2-Hydroxy-4-octyloxybenzophenone 0.2%

[0171] 2-Hydroxy-4-n-octyloxybenzophenone, UV-531 (BP-12)〔content〕≥99%; transmittance 450nm>90%500nm>95%, is an excellent high-efficiency anti-aging agent with the characteristics of light color, non-toxicity, good compatibility, low migration, easy processing, etc. It has the greatest protective effect on polymers and helps to reduce color, while delaying yellowing and blocking physical property loss. In this formula system, it works together with antioxidants as an anti-yellowing anti-aging agent.

[0172] ⑧Surface modifier A polysiloxane-polyalkoxy ether copolymer, i.e. emulsified silicone oil, emulsified silicone oil: water 1:20

[0173] Polysiloxane-polyalkoxy ether copolymer, transparent water-soluble emulsified silicone oil, water-soluble silicone oil is a silicone polymer modified by a specific hydrophilic group. In addition to the high bond energy of silicone polymer compounds, soft molecular chains, and surface tension, viscosity (25℃PaS) 500-3500, refractive index (25℃) 1.440-1.450, it is a release agent for rubber and plastic products, with good demulsification properties, giving the product a smooth, bright, soft and comfortable feel. The external water-based emulsified silicone oil in this formula system ensures the anti-stickiness and smoothness of PVC particles during pelletizing and dehydration in the dehydrator.

[0174] ⑨Surface modifier B: modified silicone oil with high phenyl functional group (oily silicone oil) 2

[0175] The specific implementation steps are:

[0176] Step 1: Add EPVC paste resin and plasticizer into the reaction emulsifier disperser in accordance with the formula ratio, set the oil emulsification temperature to 120°C, and the stirring speed during coagulation to 5000r / min;

[0177] Step 2: When the condensation temperature of the reaction emulsifier disperser rises to 80°C, add the multifunctional composite toughening and elastic anti-precipitation agent, rare earth calcium zinc multifunctional composite heat stabilizer, bright release agent, antioxidant, and 2-hydroxy-4-n-octyloxybenzophenone successively, and the stirring speed is increased to 12000r / min during condensation;

[0178] Step 3: The temperature in the reaction emulsification disperser rises to 120°C, the emulsification and dispersion is completed, and the mixture is sent to the extrusion equipment by a metering pump;

[0179] Step 4: The reaction emulsified emulsion is extruded through an extruder at a specific temperature and underwater pelletized, and then dehydrated by a dehydration device;

[0180] Step 5: During dehydration, water cooling equipment is used for cooling, wherein the cooling water is water and surface modifier A (water-based emulsified silicone oil mixed in a ratio of 1:20), the water temperature is 5 degrees, and the water content of the dehydrated PVC granules is less than 1%;

[0181] Step 6: The dehydrated ultra-soft PVC particles are dried and anti-sticked by the three-stage fan. After being dried by the first and second stage fans, they enter the third stage fan. The surface modifier B is atomized and sent to the three-stage fan at a ratio of 2% to prevent the ultra-soft PVC particles from sticking.

[0182] Modified silicone oil with high phenyl functional group, refractive index / 25℃1.5340±0.0050, viscosity / 25℃CPS800-1400, excellent scratch resistance, dry and slippery feel, high transparency, excellent compatibility, smoothness and demoulding performance, with both external and internal lubrication functions. External lubrication can improve the processing performance of materials, improve fluidity, and reduce equipment wear. Forming a uniform lubricating layer on the plastic surface can significantly reduce the surface friction coefficient and improve wear resistance; this formula system ensures the anti-adhesion agent during the drying process, packaging and transportation of ultra-soft PVC particles. Release agent in later injection molding products. And give the product a dry and slippery feel. The two surface modifiers AB complement each other and are indispensable.

[0183] Table 1: Basic formula table of Examples 1-3

[0184]

[0185] Mechanical properties tests were performed on Examples 1-3:

[0186] Tensile properties: National standard for tensile properties GB / T 1040.1-2018. Conforms to ASTM D2240 and is tested on a GL6000-10KN universal testing machine according to national standard test methods.

[0187] Physical and chemical properties tests were performed on Examples 1-3:

[0188] 1. Melt index: GB / T 3682-2000 national standard test, in line with ASTM, ISO, JIS, CNS standards, carried out on HD-R803 melt index instrument;

[0189] 2. Hardness test: GB / T531-99 national standard, in line with DIN53505, ASTM D2240, carried out on MODEL-X hardness tester;

[0190] 3. Density: GBT / 1033.2-2010 national standard, in line with ASTM D792, ASTM D297, carried out on MH-300A plastic density meter.

[0191] Table 2: Test parameter table of Example 1

[0192]

[0193] Table 3: Test results of Example 1

[0194]

[0195] Table 4: Test parameter table of Example 2

[0196] Test No.: 000066 user: **** Test Date: ***** Original length of sample: 25 Tester: 001 Sample area: 36 Sample Name: GMVC Test temperature: 23℃ Sample model: ES15M Specimen hardness: 1A

[0197] Table 5: Test results of Example 2

[0198]

[0199]

[0200] Table 6: Test parameter table of Example 3

[0201] Test No.: 000066 user: **** Test Date: ***** Original length of sample: 25 Tester: 001 Sample area: 36 Sample Name: GMVC Test temperature: 23℃ Sample model: ES20M Specimen hardness: 10A

[0202] Table 7: Test results of Example 3

[0203]

[0204]

[0205] The PVC granules provided in this technical solution have a softness that reaches or is close to the softness index of TPE while ensuring various performance indicators. Ultra-soft, highly transparent, highly tough, highly elastic, highly transparent, highly resistant to deformation, and highly resistant to precipitation ultra-soft environmentally friendly PVC toy granules have become a reality;

[0206] On the basis of ensuring various performance indicators, the maximum oil filling ratio reaches the highest historical record of 500%-800%, and can ensure that the product does not precipitate, does not emit oil, has a comfortable feel, and has good coloring performance;

[0207] In the case of high oil filling ratio, the texture is very soft and sticky. Adding surface modifier A and surface modifier B can solve the problem of PVC particles becoming sticky.

[0208] The present invention and its implementation methods are described above, and such description is not restrictive, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design structures and embodiments similar to the technical solution without creativity, which should all fall within the protection scope of the present invention.

Claims

1. A method for preparing super soft PVC granules, characterized in that: The invention comprises the following raw materials in parts by weight: 10-15% of EPVC paste resin, 70-80% of plasticizer, 5-15% of multifunctional composite toughening and elasticizing anti-precipitation agent, 1-3% of rare earth calcium zinc multifunctional composite heat stabilizer, 0.01-0.02% of bright release agent, 0.5-1.0% of antioxidant, 0.1-0.5% of 2-hydroxy-4-n-octyloxydiphenylmethane, surface modifier A, and surface modifier B; The preparation steps are also included, specifically: Step 1: Add EPVC paste resin and plasticizer into the reaction emulsification disperser in accordance with the formula ratio, set the oil emulsification temperature to 120°C, and the stirring speed during coagulation to 500-5000r / min; Step 2: When the condensation temperature of the reaction emulsifier disperser rises to 80-90°C, add the multifunctional composite toughening and elastic anti-precipitation agent, rare earth calcium zinc multifunctional composite heat stabilizer, bright release agent, antioxidant, and 2-hydroxy-4-n-octyloxybenzophenone successively, and the stirring speed is increased to 8000-12000r / min during condensation; Step 3: The temperature in the reaction emulsification disperser rises to 120°C, the emulsification and dispersion is completed, and the mixture is sent to the extrusion equipment by a metering pump; Step 4: The reaction emulsified emulsion is extruded through an extruder at a specific temperature and underwater pelletized, and then dehydrated by a dehydration device; Step 5: During dehydration, water cooling equipment is used for cooling, wherein the cooling water is water and surface modifier A (water-based emulsified silicone oil mixed in a ratio of 1:20), the water temperature is 5 degrees, and the water content of the dehydrated PVC granules is less than 1%; Step 6: The dehydrated ultra-soft PVC particles are dried and anti-sticked by the three-stage fan. After being dried by the first and second stage fans, they enter the third stage fan. The surface modifier B is atomized and sent to the three-stage fan at a ratio of 2% to prevent the ultra-soft PVC particles from sticking.

2. The method for preparing super soft PVC granules according to claim 1, characterized in that: The invention comprises the following raw materials in parts by weight: 10% of EPVC paste resin, 75% of plasticizer, 10% of multifunctional composite toughening and elasticizing anti-precipitation agent, 2% of rare earth calcium zinc multifunctional composite heat stabilizer, 0.02% of bright release agent, 0.8% of antioxidant, 0.2% of 2-hydroxy-4-n-octyloxydiphenylmethane, surface modifier A and surface modifier B.

3. The method for preparing super soft PVC granules according to claim 1, characterized in that: The EPVC paste resin is prepared by blending a P80 paste resin with PR-G; Among them, the basic composition of PR-G is: calcium carbide, VCM, EDC, degree of polymerization: 1700±100, K value: 77.5-81.0; The basic composition of the P80 paste resin is: calcium carbide, VCM, EDC, K value: 80; degree of polymerization: greater than 2000; The ratio of PR-G: P80 paste resin is 70:

30.

4. The method for preparing super soft PVC granules according to claim 1, characterized in that: The plasticizer is one or more of hexamoll dinch, D1050 plasticizer and ESO.

5. The method for preparing super soft PVC granules according to claim 1, characterized in that: The multifunctional composite toughening and elasticity-enhancing anti-precipitation agent comprises an emulsion polymer of butadiene and acrylonitrile rubber, 2-chloro-1,3-butadiene, and di(butoxyethoxyethyl) adipate, and the formula ratio is: butadiene and acrylonitrile rubber: emulsion polymer of 2-chloro-1,3-butadiene: di(butoxyethoxyethyl) adipate = 28:5:67; The preparation method of the multifunctional composite toughening and elastic anti-precipitation agent is as follows: emulsion polymers of butadiene, acrylonitrile rubber, 2-chloro-1,3-butadiene and di(butoxyethoxyethyl) adipate are added into a reaction emulsification disperser in accordance with the formula ratio, the oil emulsification temperature is set to 70°C, the stirring speed during condensation is 200-300r / min, and the condensation temperature is raised to 65-70°C.

6. The method for preparing super soft PVC granules according to claim 1, characterized in that: The antioxidant is composed of [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester and poly(dipropylene glycol) phenyl phosphite, and the formula ratio is 0.5:0.

3.

7. The method for preparing super soft PVC granules according to claim 1, characterized in that: The surface modifier A is a polysiloxane-polyalkoxy ether copolymer, and the ratio of surface modifier A to water is 1:20; the surface modifier B is a modified silicone oil with high phenyl functional groups.

8. The method for preparing super soft PVC granules according to claim 1, characterized in that: The extruder is a twin-screw structure with a length-to-diameter ratio of 1:

60. The screw structure is a full compression section process. The temperature control is divided into three sections, including a high temperature zone, a medium temperature zone and a low temperature zone. The die temperature is 70-90°C and the pelletizing temperature is 70-90°C. Among them, the high temperature area is divided into: Zone 1 240~250℃, Zone 2 230~240℃, Zone 3 220~230℃, Zone 4 210~220℃, Zone 5 200~210℃; Medium temperature zone: zone 6 190-200℃, zone 7 170-180℃, zone 8 150-160℃, zone 9 130-140℃, zone 10 120-130℃; The low temperature zones are: Zone 11 100-110℃, Zone 12 90-100℃, Zone 13 80-90℃, Zone 14 70-80℃, Zone 15 60-70℃.

9. Use of the preparation method of super soft PVC granules according to claims 1-8 in preparing super soft PVC toy materials.

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