TWI628227B - Cross-linking composite high-performance ABS/PLA environmentally friendly green material preparation method - Google Patents

Abstract

A cross-linking composite high-performance ABS/PLA green raw green material preparation method comprises: high molecular weight PLA 30% or 50%, ABS 40 or 60%, toughener 8%, chain extender 1%, ABS recycled plastic 1%, high molecular weight PLA cracking, chain extension reaction, hydrolysis resistance design, water removal in the process, using COOH-OH end of PLA, with MAH, GMA and other functional additives for end-end modification, due to ABS processing temperature 200~ 230°C, MI 200°C 5kg: 2g/10min, PLA processing temperature 170~200°C, MI 190°C 2.16kg: 8g/10min, and then the process is mixed in a twin-screw configuration, and the flow is utilized. The chain extender controlled by the variable control and the compatibilizer can change the flow deterioration of the high molecular weight PLA, the temperature and the shear, so that the shape control can be performed, and the toughening agent can effectively improve the physical properties, and the toughening and upgrading can be performed.

Description

Cross-linking composite high-performance ABS/PLA environmentally friendly green material preparation method

The invention provides a technical field of ABS/PLA alloy, in particular to a method for preparing a cross-linked composite high-performance ABS/PLA environment-friendly green material, wherein ABS high-poly powder and PLA resin are blended and extruded. A polymer alloy technology of ABS high rubber powder/PLA blend alloy was prepared.

PLA (polylactic acid) conventional characteristics: The plastics used in electronic products on the market are mainly petrochemical products such as HIPS, ABS, PC/ABS and PC resins. To replace the above-mentioned petrochemical plastics, there are often many problems to be overcome. Take the largest mainstream plastic PLA on the market as an example. The main challenges for durable electronic products are: (1) Heat resistance of uncrystallized PLA Only at about 60 °C, not only can not pass the environmental test of electronic products, even the lowest heat-resistant conditions of shipping can not be achieved; (2) PLA has been heat-treated up to 100 °C, but there is still injection molding cycle (Cycle Time) is too long, resulting in low production efficiency, in addition to poor dimensional stability, molding shrinkage and other issues still need to be overcome; (3) PLA is a shear sensitive material, the melting strength is poor, the processing point is spent Dilute problems often occur, and the rapid decline of molecular weight is also the main cause of recovery; (4) and Compared with PC, ABS and other common electronic products, PLA's toughness or impact strength is not good, only the pressure is similar, pure PLA products are usually more susceptible to damage, not suitable for high-priced electronic products; (5) because Biodegradation/easy hydrolysis characteristics, limited service life; (6) Cost problem (as shown in Table 1), the current price of PLA is still high, but petrochemical raw materials continue to soar and synthetic technology continues to improve, this Under the circumstance, it is estimated that the price of PLA raw materials will approach petrochemical plastics such as ABS, PS and PP in the next decade, and the cheaper TPS application technology will continue to develop.

Biomass compounding technology: polymer glue, that is, two or more kinds of polymers are directly mixed into a uniform single material by melt processing, which is like an alloy. Therefore, it is also called a polymer alloy. In the field of polymer nanocomposites, the biggest difference between nano-gels and organic-inorganic nanocomposites is that nano-gels are selected because of the system, composition, and addition. Different phase behaviors due to different agents and processing conditions, such as the co-continuous phase structure produced by the two-phase polymer, can not only make the composite material have the characteristics of two polymers at the same time, but sometimes produce synergistic effects (Synergistic Effect). The performance is better than any of the phases. Although the block copolymer can also have the above characteristics, the economic benefit of the gel is generally greater than that of the new polymer.

The main methods for improving the quality of raw plastics through mixing and processing are: (1) mixing with plant fibers; (2) mixing with various additives; (3) mixing with petroleum-based plastics into raw rubber and other methods. . The design of the raw rubber is based on petroleum gum as the main substrate, forming a sponge-like network structure, which allows the easily hydrolyzed and decomposed raw materials to be coated and provides the main mechanical strength, so the endurance of the raw rubber is durable. Sex is no different from existing materials. There are many products on the market that can pass the environmental tests required by electronic products.

Polylactic acid (PLA) has good strength and rigidity, but has poor flexibility and impact resistance. It is a hard and brittle material at room temperature, such as polypropylene (PP), polystyrene (PS) and poly. For the wide application of materials such as polyethylene glycol diester (PET) in films, sheets, bottles and various thermoformed and injection molded products, it is necessary to toughen and modify acrylonitrile-butadiene-styrene copolymerization of PLA. The material (ABS) has the advantages of impact resistance, high surface hardness, good chemical and electrical resistance, and easy processing. However, PLA and general-purpose ABS resins are incompatible systems, and the processability and physical and mechanical properties of the blend systems are poor. At present, the research reports on ABS/PLA blending at home and abroad are more less. ABS high rubber powder is a tough material with high rubber phase (PB rubber particle) content. It has better toughness than ABS and has good compatibility with various polymers. If it can be used, PLA and ABS high rubber powder are very good. The mixing method can obtain a blending system with better compatibility, that is, a high toughness PLA composite material can be obtained, and the process route can be simplified and the cost can be reduced.

A conventional technique such as Chinese Patent Application No. 201310310723.7 "Manufacturing Method of Macromolecular Compatibilizer for ABS/PLA Alloy Material", which mentions that the compatibilizer is composed of styrene substances 5-40, A copolymer obtained by bulk polymerization, solution polymerization or suspension polymerization of epoxy type 0.5-10, initiator type 0.1-5. The copolymer is melt-blended with short-chain PLA, wherein the short-chain PLA mass fraction is 1-95, and a macromolecular compatibilizer is obtained, which is based on the structure of the comb-type macromolecule and is improved by the polystyrene structure of the main chain. The compatibility with ABS, and the branched polylactic acid segment improves the compatibility with the polylactic acid phase, and plays a good role in the compatibilization of the two phases of ABS and PLA, which can greatly improve the blend. The mechanical properties, melt stability and processing properties, of which short-chain PLA can be replaced by industrial PLA, reduce production, improve material utilization and save energy.

Therefore, in view of the problems existing in the above-mentioned conventional structure, how to develop an innovative structure that is more ideal and practical, the consumers are eagerly awaiting, and the relevant industry must strive to develop the goal and direction of breakthrough.

In view of this, the inventor has been engaged in the manufacturing development and design experience of related products for many years, and has designed and carefully evaluated the above objectives. After the evaluation, the invention is finally practical.

The main object of the present invention is to provide a cross-linking composite high-performance ABS/PLA environmentally-friendly green material preparation method, wherein ABS high-adhesive powder/PLA blend alloy is prepared by blending and extruding ABS high-adhesive powder and PLA resin. .

In order to achieve the above object, the present invention provides a method for preparing a cross-linked composite high-performance ABS/PLA environmentally friendly green material, which comprises: high molecular weight PLA 30 or 50%, ABS 40 or 60%, toughener 8%, chain extension 1%, ABS recycled plastic 1%, high molecular weight PLA cracking, chain extension reaction, hydrolysis resistance design, water removal in the process, using COOH-OH end of PLA, with MAH, GMA and other functional additives for end-end modification , because ABS processing temperature is 200~230°C, MI 200°C 5kg: 2g/10min, PLA processing temperature is 170~200°C, MI 190°C 2.16kg: 8g/10min, and then the process is carried out in a twin-screw configuration. Mixing, and using the chain extender with rheology control and compatibilizer to change the flow deterioration of high molecular weight PLA, temperature and shear, so that it can be controlled by morphology, and the toughening agent can effectively improve the physical properties. Toughness modification.

The above-mentioned objects, structures and features of the present invention will be described in detail with reference to the preferred embodiments of the present invention. .

10‧‧‧Knife processing range

CE-1‧‧‧PLA+ chain extender-1

CE-2‧‧‧PLA+ Chain Extender-2

CE-3‧‧‧PLA+ chain extender-3

CE-4‧‧‧PLA+ chain extender-4

AP-107‧‧‧ alloy code

AP-113‧‧‧ alloy code

AP-114‧‧‧ alloy code

AP-140‧‧‧ alloy code

AP-146‧‧‧ alloy code

AP-150‧‧‧ alloy code

The first figure is a schematic diagram of the structure of the MBS resin.

The second figure is a schematic diagram of the end-capping modification of the COOH-OH end of PLA with a functionalized additive.

The third figure is a schematic diagram comparing the viscosity-increasing properties of the chain extender on PLA.

The fourth figure is a schematic diagram of the morphological changes of four chain extenders.

The fifth figure is the ABS/PLA alloy formula.

The sixth picture is a schematic photomicrograph of the finished ABS/PLA alloy.

The seventh picture is the screw configuration diagram.

The invention provides a designer of a cross-linking composite high-performance ABS/PLA environment-friendly green material preparation method.

In order to enable your review committee to have a better understanding and understanding of the purpose, features and effects of the present invention, the implementation method and the drawings are detailed as follows: Thermal Melt Index (MI): The melt index is a representation of the processing of plastic materials. Indicator of liquidity. The larger the MI value, the better the processing fluidity of the plastic material, and vice versa. The most common test standard is ASTM D1238. The MI value can be used as a reference for judging the molecular weight of the plastic. Material and processing trade-offs. The sample was placed in a fixed diameter and length die at a set pressure and temperature, and the weight (g/10 min) flowing out per unit time was measured to indicate the fluidity of the material. MI (g/10min) = collected sample weight (g) / Collection time (sec) × 600 sec.

MMA: methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3, a colorless liquid formed by esterification of methacrylic acid (MAA) with methanol. A monomer of plastic polymethyl methacrylate (PMMA).

MAA: methacrylic acid (MAA), structural formula H2C=C(CH3)COOH, methacrylic acid is a colorless transparent liquid at normal temperature. Soluble in hot water, ethanol and most organic solvents. Easy to aggregate. Its vapor can form an explosive mixture with air. It is moderately toxic and has strong irritation to skin and mucous membranes, but no carcinogenicity.

ST: Styrene (ST).

GMA: glycidyl methacrylate, which chemically reacts with the acid group (-COOH) and hydroxyl (-OH) functional groups on PLA to carry out end-capping modification.

EMA: Ethyl methacrylate.

The chain extender is MMA-MAA-St-GMA-EMA copolymer.

ABS: Acrylonitrile Butadiene Styrene (ABS), high impact strength and good toughness.

PLA: Polylactic acid (PLA), a thermoplastic material that is biodegradable and decomposes into water and carbon dioxide.

MI: Melt index, English name is melt index, will be plastic The weight of the plastic material flowing out in an iron pipe at a certain temperature (°C) and load (1200g, 2160g, 5000g) within 10 minutes is the test standard set by ASTM (Perspective Test Specification) D1238.

MAH: A maleic anhydride functional group that undergoes a chemical reaction with an acid group (-COOH) and a hydroxyl (-OH) functional group on PLA to carry out end-capping modification.

Since PLA is water-based, ABS is oily, and it is necessary to add a functional group that can combine the two. This is functionalization, and the chain extender is a medium containing a functional group. This reaction is like a soap. The water phase and the oil phase are combined to solve the processing temperature of the PLA, hydrolysis resistance and shear resistance.

The raw material PLA reaction modification technology, the present invention will start from the three aspects of thermal decomposition, hydrolysis, and the molecular weight of the material itself caused by the melt melting of the polyester system.

(1) PLA cracking and hydrolysis problem: The terminal acid group of the ester-based plastic PLA is the main cause of the molecular weight drop during processing. The polymer chain scission will generate more terminal acid groups, which makes the cracking reaction more accelerated. Therefore, in order to reduce the terminal acid group, in addition to the need to reliably remove water in the process, the use of high molecular weight PLA can effectively improve the cracking situation at the beginning, and finally the hydrolysis-resistant formulation is also introduced in the present invention to increase the service life of the terminal product.

(2) Processing window difference: difference between processing window of ABS and PLA As follows, ABS processing temperature is 200~230°C, MI 200°C 5kg: 2g/10min is the MI value of ABS, which means that the weight of plastic material flowing out within 10 minutes under the pressure of 5kg is 2g, and the ABS needs to be 200~230°C. Processing, its melt viscosity is high, PLA processing temperature is 170~200°C, MI 190°C 2.16kg: 8g/10min is the MI value of PLA, which means that the weight of plastic material flowing out within 10 minutes is 8g under the pressure of 2.16kg. The processing temperature of PLA is 170~200°C, and the processing viscosity and melt strength are both low. If it is not improved, the domain size of the composite will be too large, which will cause the physical property to drop rapidly. In order to overcome this problem: in addition to the need to use the appropriate screw configuration, temperature, shear force for melt mixing, the molecular weight of PLA needs to be further improved to improve the melt viscosity. ABS will use a rheological modification formula to further narrow the viscosity of the two-phase polymer and the processing window to improve the mixing quality.

(3) Two-phase compatibility problem: ABS is a lipophilic polymer, while PLA is hydrophilic, and the two phases of rejection will greatly reduce the overall toughness. It is known that the compatibility between PLA and PMMA is good. If the MBS resin as shown in the first figure or the polyfunctional reaction type additive using the terminal reaction of PLA is used, the structure of the two additives is similar to that of ABS. The modification of PLA by the additive will effectively improve the compatibility of the two phases of ABS and PLA, and further enhance the physical properties.

The present invention will use the reaction ejecting method while overcoming the hydrolysis problem and increasing the compatibility of the two phases. The technical content thereof is as shown in the above figure, PLA has a higher acid value/alcohol value, and the terminal functional group easily provides active H+, which is triggered. Polymer hydrolysis chain scission, the present invention will use German additive technology, using a reactive compatibilizer with multiple epoxy functional groups, and End-capping with the terminal carboxyl group of the polymer, in addition to increasing the molecular weight, As a hydrolysis stabilizer, and improve the compatibility between the two phases. When PLA is melt processed, especially when mixed with engineering plastic ABS with high processing temperature to prepare a composite material, the terminal acid group will attack the main chain, which will generate more terminal acid groups. The acid-based reaction additive can further prevent the molecular weight of the PLA from rapidly decreasing, and further increase the molecular weight, processing viscosity and compatibility. A large amount of Glycidyl methacrylate (glycidyl methacrylate) functional group of such additives can react with the PLA in the chain of the mixing process to achieve viscosity control. In the mixing study, the appropriate rheological PLA is paired with the correct specification of ABS to simulate and evaluate the optimal processing window of the two-phase polymer for shear dispersion or tensile flow dispersion, using TSE/SSE (double Screw Extruder / Single Screw Extruder) EFM (Stretched Flow Mixer) is used to produce ABS/PLA alloy materials of sufficient strength.

The invention provides a cross-linking composite high-performance PLA-ABS environmentally-friendly green material preparation method, which comprises: PLA cracking, PLA cracking to reduce terminal acid groups, using high molecular weight PLA, chain extension reaction, hydrolysis resistance design, and process Indeed, in addition to water, the COOH-OH end of the PLA is end-capped with a functional additive such as MAH or GMA (as shown in the second figure). The process adopts twin-screw configuration design, suitable When the mixing temperature and shearing, and the use of high molecular weight PLA, rheology modification formula, in which a screw processing ABS processing temperature is 200 ~ 230 ° C, melt index (MI) 200 ° C, 5kg: 2g/10min, another The processing temperature of the PLA in the screw is 170-200 ° C, the melt index (MI) is 190 ° C, 2.16 kg: 8 g/10 min.

Referring to the third figure, the chain extender is compared to the viscosity-increasing performance of PLA. The X-axis is the shear rate (1/s) and the Y-axis is the viscousity (pa.S). PLA+ Chain extender-1 is (CE-1), PLA+ chain extender-2 is (CE-2), PLA+ chain extender-3 is (CE-3), and PLA+ chain extender-4 is (CE-4). The square of the label is in the kneading processing range of 10. As can be seen from the figure, the chain extender-1 has a better flow. Chain extender-2 has better shear resistance. However, chain extender-3, chain extender-4 has a poor chain extension effect, which may be caused by a higher acid group.

Referring to the fourth figure, the morphological changes of the four chain extenders were observed by electron microscopy (SEM), code AP-107 (chain extender-1), code AP-113 (chain extender-2), code AP -114 (chain extender-3), AP-140 (chain extender-4), wherein the code AP-114 (chain extender-3), AP-140 (chain extender-4) has obvious phase separation The interface, code AP-113 (chain extender-2) has good compatibility, the best physical property code AP-107, the alloy coded AP-113 is observed by electron microscopy (TEM), and the code AP-113 is observed. The chain extender-2) has a smaller domain size and better compatibility, and the phase thickness is 0.5 to 1 μm.

Referring to the fifth and sixth figures, the cross-linked composite high-performance ABS/PLA environmentally-friendly green material preparation method, wherein the reference group is 100% of ABS-2 raw material, and its physical property is Izod impact strength (izod impact) Stength) 24.5 (kg-cm/cm), flexural modulus 20000 (kg/cm ² ), tensile strength (tensile stength) 400 (kg/cm ² ), heat distortion temperature (HDT ° C, 66 psi) 87 °C, melt index (MI) 5 (g/10 min, 200 ° C, 5 kg), biomass content 0%. Alloy 1 is coded AP-146, formula is 60% for ABS-2, 30% for PLA-1, 8% for toughener-2, 1% for chain extender-2, and 1% for ABS recycled plastic. The physical properties are izod impact stength 44.6 (kg-cm/cm), flexural modulus 21957 (kg/cm ² ), tensile strength (tensile stength) 421 (kg/cm ² ), The heat distortion temperature (HDT ° C, 66 psi) was 88.2 ° C, the melt index (MI) was 7.04 (g/10 min, 200 ° C, 5 kg), and the biomass content was 30%. Alloy 2 is coded AP-150, formula is 40% for ABS-2, 50% for PLA-1, 8% for toughener-2, 1% for chain extender-2, and 1% for ABS recycled plastic. The physical properties are izod impact stength 35.3 (kg-cm/cm), flexural modulus 28233 (kg/cm ² ), tensile strength (tensile stength) 457 (kg/cm ² ), The heat distortion temperature (HDT ° C, 66 psi) was 80.8 ° C, the melt index (MI) was 9.34 (g/10 min, 200 ° C, 5 kg), and the biomass content was 50%. Among them, chain extender-2 has the function of rheology control and compatibilizer, the domain size is small, the compatibility is better, and the phase thickness is 0.5~1μm. With a certain composition of toughening agent, physical properties can be effectively improved. When the PLA content is 30%, the izod impact stength is 44.6 (kg-cm/cm).

The hot melt index (MI) of the alloy of the present invention has a MI value greater than 15g/10min. The minimum size of the conventional PLA in the production of the product casing or the fixed PIN pin is 1 to 1.2 mm, and the ABS/PLA alloy of the present invention can reach 05 to 0.9 mm. The impact resistance coefficient of the PLA at normal temperature is 2, and the ABS/PLA alloy of the present invention can reach a low temperature of -40 degrees, and the notched impact resistance coefficient is 40. The ABS/PLA alloy of the present invention is in compliance with the EPEAT environmental protection specification. EPEAT Environmental Code: In July 2006, the Electronic Product Environmental Assessment Tool (EPEAT), published by the US Environmental Protection Agency to assess whether electronic products have good environmental performance, can help government agencies and Private companies are used as reference indicators when buying green electronics.

Referring to the seventh figure, the screw configuration diagram, the alloy material of the invention is composed of a plurality of twin-screw systems, and a combination of two screw positions is formed to form a plurality of materials and mixing sections to achieve the best alloy material. Resistance to shear, flow, strength and viscosity.

The screw processing temperature is 200~230, which is the working temperature of ABS processing, and 170~200 is the working temperature of PLA processing. The alloy of the present invention mainly needs to overcome the combination of the processing temperatures of the two materials, so that the physical properties of PLA are higher than 200 degrees. When the ABS is below 200 degrees, the rheology will not become small, resulting in incomplete melting. Therefore, the two materials are kneaded, and the chain extender is used to fuse the two materials to form a chain extension reaction, so as to improve the two materials between 170 and 230, and the physical properties do not change too much, so as to achieve the purpose of mixing the alloy. Therefore, the chain extender is a compatibilizer of two materials, which increases the mutual viscosity and neutralizes the processing difference between the two materials. The alloy of the invention increases the chain extension of the two materials Should be, the quality of MI is improved, hydrolysis resistance, and strengthening physical and crystalline chains. It can increase the fluidity of the finished product, and can make large-area and small-sized products in the cold mold (temperature of the mold itself) 40~50 degrees, such as memory card casing, TV screen casing, electronic transaction machine casing, making 3C The product is more resistant to impact, and the impact resistance and tensile resistance of the chain extender 2 are better than the original PLA, and it is also environmentally friendly.

The present invention has been described with reference to the preferred embodiments of the present invention. However, those skilled in the art can change and modify the present invention without departing from the spirit and scope of the invention. Such changes and modifications shall be covered in the scope defined by the following patent application.

In summary, the present invention provides a method for preparing a cross-linked composite high-performance ABS/PLA environmentally-friendly green material, which has indeed achieved all the objects of the present invention, and the spatial pattern of the combined structure is not found in the same product. It has not been disclosed before the application, has complied with the provisions of the Patent Law, and has applied for it according to law.

Claims (6)

A cross-linking composite high-performance ABS/PLA environmentally-friendly green material preparation method comprises: ABS is 60%, PLA is 30%, toughener is 8%, chain extender is 1%, ABS recycled plastic is 1%, The chain extender is MMA-MAA-St-GMA-EMA copolymer, the PLA uses high molecular weight PLA, the COOH-OH end of PLA is end-capped with functionalized additives, and the ABS/PLA alloy is designed and manufactured in a twin-screw configuration. ABS processing temperature 200~230 °C, hot melt index (MI) 200 °C 5kg: 2g/10min, is the MI value of ABS, refers to the weight of plastic material flowing out within 10 minutes under the pressure of 5kg, PLA processing temperature 170~200°C, hot melt index (MI) 190°C 2.16kg: 8g/10min, which is the MI value of PLA, which means that the weight of the plastic material flowing out within 10 minutes is 8g under the pressure of 2.16kg, and then the process is The twin-screw configuration method, suitable mixing, and using the chain extender with rheology control and compatibilizer to change the metamorphism of high molecular weight PLA, temperature and shear, so that it can be controlled by morphology and toughened. The agent can effectively improve the physical properties, and the toughening and upgrading is carried out. The twin-screw system is composed of a plurality of twin-screw systems, and the position of each twin-screw position is adjusted. Combined to form a plurality of prime materials kneading section, the present invention is to achieve the ABS / PLA alloy material best shear resistance, flowability, strength and viscosity. The method for preparing a cross-linked composite high-performance ABS/PLA environmentally-friendly green material according to the first aspect of the invention, wherein the functionalized additive is one of functional additives such as MAH and GMA. The method for preparing a crosslinked composite high-performance ABS/PLA environmentally friendly green material according to claim 1, wherein the ABS/PLA alloy material has a heat melt index (MI) value of more than 15 g/10 min. A cross-linking composite high-performance ABS/PLA environmentally-friendly green material preparation method comprises: ABS 40%, PLA 50%, toughener 8%, chain extender 1%, ABS recycled plastic 1%, The chain extender is MMA-MAA-St-GMA-EMA copolymer, the PLA uses high molecular weight PLA, the COOH-OH end of PLA is end-capped with functionalized additives, and the ABS/PLA alloy is designed and manufactured in a twin-screw configuration. ABS processing temperature 200~230 °C, hot melt index (MI) 200 °C 5kg: 2g/10min, is the MI value of ABS, refers to the weight of plastic material flowing out within 10 minutes under the pressure of 5kg, PLA processing temperature 170~200°C, hot melt index (MI) 190°C 2.16kg: 8g/10min, which is the MI value of PLA, which means that the weight of the plastic material flowing out within 10 minutes is 8g under the pressure of 2.16kg, and then the process is The twin-screw configuration method, suitable mixing, and using the chain extender with rheology control and compatibilizer to change the metamorphism of high molecular weight PLA, temperature and shear, so that it can be controlled by morphology and toughened. The agent can effectively improve the physical properties, and the toughening and upgrading is carried out. The twin-screw system is composed of a plurality of twin-screw systems, and the position of each twin-screw position is adjusted. Combined to form a plurality of prime materials kneading segments, to achieve the best alloy material of the present invention, shear resistance, flowability, strength and viscosity. Cross-linked composite high performance as described in claim 4 ABS/PLA environmentally friendly green material preparation method, wherein the aforementioned functionalization additive is one of functional additives such as MAH and GMA. The method for preparing a crosslinked composite high-performance ABS/PLA environmentally friendly green material according to claim 4, wherein the ABS/PLA alloy material has a heat melt index (MI) value of more than 15 g/10 min.