CN107541004B

CN107541004B - Load-resistant and fatigue-resistant TPE (thermoplastic elastomer) and preparation method thereof

Info

Publication number: CN107541004B
Application number: CN201610494401.6A
Authority: CN
Inventors: 张桦; 汪洋; 姜洪颖; 王晶; 张新华; 李静; 孙丽朋; 王秀丽; 刘浩; 刘容德; 王晓敏; 桂俊杰
Original assignee: China Petroleum and Chemical Corp
Current assignee: China Petroleum and Chemical Corp
Priority date: 2016-06-29
Filing date: 2016-06-29
Publication date: 2020-05-12
Anticipated expiration: 2036-06-29
Also published as: CN107541004A

Abstract

An anti-load and anti-fatigue TPE thermoplastic elastomer and a preparation method thereof, belonging to the technical field of high polymer materials. The elastomer is characterized by comprising the following components in parts by weight: 46-50 parts of SEBS, 8-12 parts of POE (polyolefin elastomer), 16-20 parts of PP (polypropylene copolymer), 28-32 parts of liquid polybutylene PB (polybutadiene), 0.4-0.8 part of antioxidant and 11-15 parts of calcium carbonate, and 0.6-0.8 part of processing lubricant. The preparation method comprises the steps of weighing most of materials, mixing the materials in a high-speed mixer, heating to 65-75 ℃, adding liquid polybutene, continuously mixing at high speed, stopping stirring when liquid phase components are completely absorbed by the mixed materials, and granulating the mixed materials after cooling. Compared with the TPE material of the prior invention, the TPE material has good load-resistant fatigue-resistant performance; the hub outer cladding material has good rebound resilience and strong binding power, and the time of being crushed is far longer than that of the TPE material of the prior invention.

Description

Load-resistant and fatigue-resistant TPE (thermoplastic elastomer) and preparation method thereof

Technical Field

An anti-load and anti-fatigue TPE thermoplastic elastomer and a preparation method thereof, belonging to the technical field of high polymer materials.

Background

Thermoplastic elastomer (TPE) is an elastomer that combines rubber elasticity with thermoplastic processability. Because the TPE material is environment-friendly, nontoxic and safe, has excellent colorability and soft touch, has better weather resistance, fatigue resistance and temperature resistance, has excellent processing performance, can be recycled, and can effectively reduce the use cost. In addition, because vulcanization is not needed in the production process, the production flow is greatly simplified, and the energy consumption is effectively reduced. The TPE material can be subjected to secondary injection molding, is coated and bonded with matrix materials such as PP, PE, PC, PS, ABS and the like, and can also be formed independently. Compared with the traditional thermosetting rubber, the thermoplastic elastomer has the advantages of simple forming and processing, reusable material, high cost performance, small environmental pollution and the like. The TPE material has excellent performance, so that the TPE material is more and more widely applied to the fields of daily necessities, medical treatment, electronic and electric appliances, communication, automobile industry and the like in recent years.

In the prior art, a high-resilience TPE thermoplastic elastomer and a preparation method thereof comprise the following components in percentage by mass: 39-49% of SEBS, 5-10% of homopolymerized PP, 30-40% of white oil, 5-9% of simethicone, 4-8% of calcium carbonate, 0.2-0.4% of lubricant and 0.2-0.4% of antioxidant. In addition, elastic fiber is added, so that the elastic recovery capability of the system is improved, and the impact resistance, creep resistance and deformation recovery capability of the whole body are modified. The material has excellent resilience, no toxicity, environmental protection, good processing performance and smooth surface, can be used for manufacturing high-requirement medical products, and has lower cost. The TPE plastic comprises the following components in parts by weight: SEBS 15-25 parts, EPDM 15-25 parts, elastomer 5-15 parts, PA 661-10 parts, TPV 10-20 parts, and white oil 20-35 parts. The prepared TPE plastic has the advantages of low price, high yield, excellent performance, accordance with different requirements of customers and environmental protection. The TPE material consists of the following components in parts by weight: 18-22 parts of PP resin, 23-27 parts of first TPE elastomer, 3-7 parts of second TPE elastomer, 8-12 parts of POE elastomer, 13-17 parts of solid halogen-free flame retardant, 13-17 parts of liquid halogen-free flame retardant, 3-5 parts of quartz powder, 3-5 parts of EPDM, 0.6-1.0 part of vulcanizing agent, 0.1-0.3 part of cross-linking agent, 0.4-0.6 part of coupling agent, 0.1-0.3 part of antioxidant, 0.1-0.2 part of first light stabilizer and 0.1-0.2 part of second light stabilizer. The halogen-free flame-retardant thermoplastic elastomer TPE material prepared by the invention has the high elastic performance of the traditional rubber and the thermoplastic processing performance of resin, has good adaptability and economy, and can be processed for many times and recycled. And the super cold-resistant torsion-resistant elastomer TPE sheath material for the wind energy cable comprises elastomer resin, polyolefin resin, white oil, a compatilizer, an antioxidant, a filler and a processing aid. The preparation method comprises the steps of taking elastomer resin as a base material, adding other raw material components, uniformly mixing, then forcibly feeding the mixture into a double-screw extruder, extruding, granulating and drying. The elastomer TPE sheath material does not contain halogen, heavy metal elements and the like, is harmless to the environment, can be recycled repeatedly, has particularly good cold resistance and torsion resistance, and is suitable for producing various wind energy cables with soft requirements. The thermoplastic elastomer comprises, by weight, 30-60 parts of SEBS, 2-6 parts of a stabilizer, 10-15 parts of a filler, 30-80 parts of white oil, 3-6 parts of an anti-UV agent and 6-10 parts of polypropylene. The product can be used for preparing TPE and TPR crude rubber particles suitable for various fields according to different formulas, and can be divided into PP rubber coating, ABS/PC alloy rubber coating, PA rubber coating, wire and cable extrusion, medical film blow molding and the like according to different applications, the product has very good cold-resistant effect, can keep elasticity at-56 ℃, has excellent environmental protection performance, can pass international various strict environmental protection and food sanitation tests, and is widely applied to the fields of toys, infant and children products, automobile accessories, household articles, medical products, tools, electric appliance accessories and the like. The prior art is mainly improved from the aspects of high elasticity, impact resistance, low temperature resistance, flame retardance, no halogen, environmental protection and repeatable recycling of TPE thermoplastic elastomer. However, the performance of the TPE thermoplastic elastomer which needs weather resistance and load resistance when being used in the engineering field is not solved by the prior art; but also has obvious defects in the adhesive property with PP, ABS and other materials.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: overcomes the defects of the prior art, and provides a load-resistant and fatigue-resistant TPE thermoplastic elastomer which has good adhesive property with PP, ABS and other materials and a preparation method thereof.

The technical scheme adopted by the invention for solving the technical problems is as follows: the load-resistant and fatigue-resistant TPE thermoplastic elastomer is characterized by comprising the following components in parts by weight: 46-50 parts of SEBS, 8-12 parts of POE (polyolefin elastomer), 16-20 parts of PP (polypropylene copolymer), 28-32 parts of liquid polybutylene PB (polybutadiene), 0.4-0.8 part of antioxidant and 11-15 parts of calcium carbonate, and 0.6-0.8 part of processing lubricant.

The invention relates to a PP/POE/SEBS/PB quaternary blend elastomer, wherein a copolymerization polypropylene and SEBS are used as main raw materials to prepare a load-resistant and fatigue-resistant TPE thermoplastic elastomer. SEBS is a linear triblock copolymer with polystyrene as a terminal segment and an ethylene-butylene copolymer obtained by hydrogenation of polybutadiene as a middle elastic block. SEBS does not contain unsaturated double bonds, so that the SEBS has good thermal stability and weather resistance; the POE elastomer molecular structure contains side octyl of short chain, can form a junction point in the molecular structure to play a role in connection and buffering among PP/SEBS molecules, the copolymerized polypropylene contains a small amount of ethylene chain segments, and POE can effectively cooperate with the compatibility of SEBS and copolymerized PP, so that a PP dispersed phase has a more uniform dispersion size and a good dispersion level in an SEBS continuous phase; according to the macroscopic properties of the material, after 8-12 parts of POE elastomer is added into a PP/SEBS blending system, the tensile strength and the elongation at break strain of the PP/POE/SEBS ternary blend are greatly improved compared with those of the PP/SEBS binary blend system. Compared with the common softening agent (such as white oil and naphthenic oil) used in the prior patent, the liquid polybutene serving as the softening agent for preparing the TPE elastomer has the advantages of good compatibility with PP/POE/SEBS, difficult precipitation and high molecular weight, enables a plasticized PP/POE/SEBS/PB system to have more excellent load resistance and tear resistance, can effectively improve the wear resistance and fatigue resistance of the prepared TPE elastomer, can be used as an outer coating layer of a solid ABS tire and a high-grade travel suitcase PP hub, can improve the bonding strength between the TPE and the ABS or PP when the liquid polybutene is applied to the TPE elastomer, enables the TPE elastomer to have higher bonding force when being used as the outer coating layer of the ABS or PP wheel, and enables the coated TPE elastomer layer to be less prone to fall off from the ABS or PP hub.

Preferably, the SEBS contains 29-35% of styrene, 75-79% of Shore hardness and 24-27 MPa of tensile strength at break, and the weight part of the SEBS is 46-48 parts. SEBS is a linear triblock copolymer which takes polystyrene as a terminal segment and takes an ethylene-butylene copolymer obtained by hydrogenating polybutadiene as a middle elastic block, and the product brand can be TAIROL3150 of Taiwan rubber or 502 and 503 of Yuanization.

Preferably, the content of octene in the POE elastomer is 18% -25%, and the Mooney viscosity ML of the POE elastomer at 120 DEG C₁₊₄5-8 parts of POE elastomer, 9-10 parts of POE elastomer. The reagent can be selected from 8210 of Exxon Mobil, USA, and 8200 of DuPont-Dow chemical company, USA.

Preferably, the copolymerized PP is ethylene copolymerized polypropylene, the melt flow rate is 8-12, and the weight part of the copolymerized PP is 16-18. The product SP-179 of Qilu's China petrochemical company can be selected.

Preferably, the average molecular weight of the liquid polybutene is 950-1300. The product can be PB-1300 from Korean Dalin, or H-100 from Enlishi.

After the components of the PP/POE/SEBS/PB quaternary blending elastomer are optimized, the synergistic effect of the components can reach the optimal state, so that the performances of the final product are optimal.

Preferably, the antioxidant is a composite antioxidant of pentaerythritol tetrakis [ β - (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] and tris (2, 4-di-tert-butylphenyl) phosphite in a ratio of 2:1 or 3: 2.

Preferably, the calcium carbonate is 2500-mesh active light calcium carbonate. The addition of the light activated calcium carbonate is more beneficial to ensuring the dimensional stability of the product after molding.

Preferably, the processing lubricant is glyceryl distearate. The glyceryl distearate is more favorable for demolding in the product processing process.

The preparation method of the load-resistant and fatigue-resistant TPE thermoplastic elastomer is characterized by comprising the following steps: weighing SEBS, POE elastomer, PP copolymer, antioxidant and processing lubricant according to parts by weight, putting the weighed materials into a high-speed mixer with the rotating speed of 1000 r/min-1400 r/min, mixing, heating to 65-75 ℃, slowly adding liquid polybutene, continuously mixing at high speed, stopping stirring until liquid phase components are completely absorbed by the mixture, adding calcium carbonate, continuously stirring for 2-3 min, cooling after the mixture is not bonded and uniformly dispersed, and granulating the mixed material after cooling.

The invention has the advantages that: the TPE elastomer prepared by the SEBS, the POE and the copolymerized PP under the plasticizing effect of the liquid polybutene and the performance of the quaternary blend compensate and promote each other. The copolymerized PP is used as a framework material consisting of TPE, so that the TPE is endowed with higher tensile strength, and the extremely high melt flow rate provides better injection molding fluidity for the TPE. The phase state of PP/POE/SEBS after melt blending reaches perfect homogenization combination. The TPE material has excellent load resistance and fatigue resistance in performance; the liquid polybutene mainly plays a role of a plasticizer in the quaternary blend, so that the Shore A hardness of the quaternary blend is reduced to 76-78. Compared with low-molecular plasticizers such as white oil, naphthenic oil and the like, the liquid polybutene has high molecular weight and good plasticizing performance, and the prepared TPE elastomer has high elasticity and good tear resistance; the liquid polybutene can also improve the cohesiveness of the TPE elastomer, and the TPE elastomer can be effectively bonded on a PP or ABS wheel hub when being used as a PP wheel outer coating material, and is not easy to fall off from the wheel hub for a long time under high load.

Compared with the prior art, the load-resistant and fatigue-resistant TPE thermoplastic elastomer and the preparation method thereof have the beneficial effects that: compared with the TPE material of the invention, the TPE thermoplastic elastomer prepared by melt blending of the PP/POE/SEBS/PB copolymer has better load resistance and fatigue resistance; the TPE material disclosed by the invention can be used as an outer covering material of a PP or ABS hub, can be effectively bonded on a PP wheel, and has the advantages of good rebound resilience, strong bonding force and long-time high-load test, and the time for being crushed is far longer than that of the TPE material disclosed by the invention. The composite material can be used for coating the outer layers of solid tires and high-grade travel case wheels, and has the effects of shock absorption and noise reduction.

Detailed Description

The load and fatigue resistant TPE thermoplastic elastomer and the preparation method thereof according to the present invention will be further described with reference to the following specific examples, wherein example 1 is the best example.

The example formulation components of the load and fatigue resistant TPE elastomer are shown in table 1. Of these, example 3 is the best mode.

TABLE 1 examples 1-5 parts by weight of load and fatigue resistant TPE elastomer formulation

TAIROL3150 taking SEBS as a table rubber in examples 1-3, 502 taking SEBS as a clouded rubber in example 4, 503 taking SEBS as a clouded rubber in example 5, wherein the styrene content in the SEBS is 29-35%, the Shore A hardness is 75-79, and the tensile strength at break is 24-27 MPa; in examples 1 to 3, the POE elastomer had an octene content of 18 to 25% and a Mooney viscosity ML at 120 ℃₁₊₄5-8 parts of POE elastomer, 9-10 parts of POE elastomer. The melt flow rate of SP-179 is 8-12, and the weight part of the copolymerized PP is 16-18; the average molecular weight of the liquid polybutene in examples 1 to 3 was 1200, the average molecular weight of the liquid polybutene in example 4 was 950, and the average molecular weight of the liquid polybutene in example 5 was 1300.

Comparative examples 1 to 8 are comparative formulations, and the component ratios of the comparative formulations are shown in table 2.

TABLE 2 examples 1-8 formulations (in parts by weight) of load-resistant, fatigue-resistant TPE elastomers

Weighing the materials according to a formula in the examples and the comparative examples, weighing the materials according to a certain proportion, putting the SEBS, the POE, the SP-179, the SP-1010, the POS-168 and the glyceryl distearate into a high-speed mixer together for mixing, slowly adding the liquid polybutene when the temperature of the materials reaches 65-75 ℃, continuously mixing at high speed, stopping stirring and adding the calcium carbonate when the liquid phase components are completely absorbed by the mixture, continuously stirring at high speed for 2-3 minutes, cooling the mixture in a low-speed mixer after the mixture is not bonded and uniformly dispersed, and discharging the materials when the temperature of the materials is lower than 60 ℃. The blended material was pelletized in a twin screw extruder to produce TPE elastomer pellets with the pelletizing parameters set forth in table 3.

TABLE 3 granulator parameter settings

After drying the granules, pressing sample pieces of 200mm multiplied by 2mm by a press, then punching into II type tensile sample strips and pant type tearing sample strips by a die punching machine, and testing the tensile property and the tearing property by a tensile machine. And pressing a sample sheet with the thickness of 50mm multiplied by 6mm by a press, and measuring the Shore A hardness of the TPE material by using a Shore A hardness tester. And (3) a mould pressing process: plasticizing for 3min according to a plasticizing process, keeping the temperature at 190 ℃ and the pressure at 10-15 MPa for 3 min.

And the injection molding machine is used, and the insert injection molding process is adopted to perform injection molding on the dried TPE granules to wrap the PP wheel, so that the shock absorption effect is realized on the PP case wheel. The insert molding process is shown in table 4.

TABLE 4 injection molding machine parameter settings

Insert injection molded wheel (i.e. TPE coated PP wheel) resistance to load failure test: the insert injection molding wheel is arranged on a case, 100kg of load is loaded in the case, the metal tubes are placed in an arrangement mode rotating at the linear speed of 60m/min, and the time from the beginning of placement to the time when the TPE coating layer is layered or separated from the PP wheel is recorded.

The results of the performance tests of the examples and comparative examples of the load-and fatigue-resistant TPE and insert injection molded wheel are shown in table 5.

TABLE 5 comparison of the performance of the load-resistant and fatigue-resistant TPE and insert injection molded wheels

The test results of the examples and comparative examples show that: the hardness of the TPE material prepared by using the POE8402 with low content of homopolymerized polypropylene or octene and small Mooney viscosity exceeds the material requirement, and the prepared elastomer has poor coating adhesion with a PP wheel and is easy to separate from the PP wheel due to poor compatibility of the homopolymerized polypropylene or the POE8402 with SEBS and PB 1300. Compared with PB-1300, the molecular weight of white oil/naphthenic oil/aromatic oil and the like is small, the hardness of the prepared TPE elastomer is small, the load damage resistance time of the insert injection molding PP wheel is short, and the insert injection molding PP wheel is easy to separate from the PP wheel. The TPE thermoplastic elastomer prepared only under the condition of melt blending of the copolymerized PP/POE/SEBS/PB has good load-resistant fatigue-resistant performance; the TPE material can be used as an outer coating material of a PP or ABS wheel hub, can be effectively bonded on the PP wheel, and has the advantages of good rebound resilience, strong bonding force and long-time high-load test, and the time for being crushed is far longer than that of the TPE material of the prior invention.

The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.

Claims

1. The load-resistant and fatigue-resistant TPE thermoplastic elastomer is characterized by comprising the following components in parts by weight: 46 parts of SEBS, 10 parts of POE elastomer, 18 parts of PP copolymer, 28 parts of liquid polybutene PB, 0.5 part of antioxidant, 14 parts of 2500-mesh active light calcium carbonate and 0.7 part of glyceryl distearate; the SEBS is TAIROL3150 of the rubber, the content of octene in the POE elastomer is 18% -25%,mooney viscosity ML at 120 ℃ of POE elastomer₁₊₄5-8, the copolymerized PP is ethylene copolymerized polypropylene, the melt flow rate is 8-12, the average molecular weight of the liquid polybutene is 1200, and the antioxidant is 0.3 part by weight of tetrakis [ β - (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid]Pentaerythritol ester and 0.2 part by weight of tris (2, 4-di-tert-butylphenyl) phosphite.

2. A process for preparing the load and fatigue resistant TPE thermoplastic elastomer of claim 1, wherein: weighing SEBS, POE elastomer, PP copolymer, antioxidant and processing lubricant according to parts by weight, putting the weighed materials into a high-speed mixer with the rotating speed of 1000 r/min-1400 r/min, mixing, heating to 65-75 ℃, adding liquid polybutene, continuously mixing at high speed, stopping stirring until liquid phase components are completely absorbed by the mixture, adding calcium carbonate, continuously stirring for 2-3 min, cooling after the mixture is not bonded and uniformly dispersed, and granulating the mixed material after cooling.