Beijing Fengyang Plasticization Engineering Technology Co., Ltd. successfully developed starch/PVA alloy

Starch/PVA alloy technology is still in the foresight technology in the world's total biodegradable technology, and the project has a high technical content. Starch is a resource that can be recycled every year. The source of raw materials is abundant, and the price is very low compared with PVA. By adding to PVA, not only can reduce the cost of raw materials, produce completely biodegradable products, and protect the natural environment on which human beings depend; at the same time, according to foreign data reports, the world’s oil and natural gas resources will be exhausted by the end of this century ( It is predicted that oil reserves will be mineable for 43 years and natural gas for 65 years. Starch/PVA alloying technology is a strategic measure to implement resource substitution and replace some non-renewable resources with renewable resources. Therefore, this technology not only expands the function of plastics, but also alleviates or mitigates the environmental contradictions to a certain extent. It is also a supplement to non-renewable resources. It is of great significance to ensure the sustainable development of the plastics industry and continuously meet the needs of society.

PVA itself has the function of biodegradation, and starch is a natural biodegradable material, which means that the product not only has good biodegradability, but also can save limited petroleum resources and can greatly reduce plastic waste, in line with the "resources from the province The principle of “grabbing and minimizing the source” means that the waste is beneficial to the composting process. It is a unique way of recycling and it is in line with the re-use of resources.

China has now included industrial biotechnologies in the “Eleventh Five-Year Plan” to increase the biological substitution of petrochemical raw materials to strategic significance, and urges the use of biomaterials to replace 10% to 15% of crude oil consumption in 2010. This will accelerate the ecological The industrialization of industrial biotechnology represented by plastics will reduce the dependence of industrial manufacturing on petroleum and promote the sustainable development of energy and resources in China. This will greatly promote the process of industrialization of ecological plastics, and has important guiding significance for the expansion of the scale of China's ecological plastics industry.

After a large number of experiments and researches, Beijing Fengyang Plasticization Engineering Technology Co., Ltd. has screened out plasticizing modifiers that can reduce the plasticization temperature of PVA. By changing the aggregation structure of PVA, the thermal stability and easy hydrolysis of PVA are improved. At the same time, the process formula was improved, PVA dry melt granulation was realized on the twin-screw extruder, and single-layer or multi-layer film products were processed on the general blown film equipment. The dry extrusion blow molding method is simple in equipment, large in production capacity, high in efficiency, low in production cost, and does not require high quality of equipment, equipment, and operators, thereby greatly promoting the application of PVA film in packaging, and filling domestic high-speed production. The blankness of PVA film can change China's long-term reliance on imports after mass production.

By modifying the readily water-soluble nature of PVA, its water resistance is improved and its water solubility is controlled at different temperatures, thereby broadening its application field. Based on this technology, Beijing Fengyang Plasticization Engineering Technology Co., Ltd. successfully developed starch/PVA alloying technology and complete sets of equipment.

The starch/PVA alloy process technology is based on the PVA modification technology (dry extrusion blow molding method), and the starch and the modified PVA are melt-extruded and pelletized through a twin-screw extruder to obtain a special material, and then the universal Equipment to produce biodegradable products. The main point of mechanical alloying is that the processing temperature must be higher than the glass transition temperature of the amorphous polymer and the melting temperature of the crystalline polymer; the twin screw extruder needs to have a sufficient temperature adjustment interval and the temperature adjustment must be guaranteed The required fluidity and shear force of the material to achieve the desired blending speed and degree of mixing, so as to ensure the molecular level interpenetrating network between starch and PVA; due to the large viscosity of the melt, mixing is slow and not easy to uniform The degree of mixing depends on the temperature, shear force and time. In addition, the extruder is preferably equipped with an exhaust device to adjust the moisture content of the material.

PVA has a high melting point and is close to the thermal decomposition temperature, and is easily decomposed at a temperature below its softening point, making it difficult to perform thermoplastic processing and adversely affecting product performance. For this reason, the production process first pre-plasticizes the PVA in a plasticizer solution to lower its melting point. When pre-plasticizing treatment, the moisture content of the material is usually controlled at 15 to 40% of PVA weight so as to avoid complete dissolution of PVA.

Its craft is:

1 First, PVA is preplasticized in a plasticizer solution to reduce its melting point;
2 Starch is the base material (40~60%), modified PVA and additives are added to the high-speed mixing equipment to improve the quality and film formation of downstream products.
3 The materials to be processed will be combined with the large aspect ratio and high shear screw combination developed by our company, two-stage mixing and granulation equipment for discharging, and the melt-kneading under high shear will be used to make starch resin and modification. The components of the PVA blend system are organically fused together and the plasticization is more uniform.
4 The special material obtained is encapsulated by vacuum equipment or directly blown on the ordinary film blowing machine. Since the raw materials contain high concentrations of hydroxyl groups, an interpenetrating network structure can be formed with good fluidity, and the film has good strength, softness, luster, gas barrier, oil resistance, solvent resistance and heat sealability.

Starch/PVA alloy can be used in injection molding (such as boxes, small containers, medical and health) in addition to garbage bags, shopping bags, transparent packaging, dangerous goods packaging bags, instant packaging bags, and industrial packaging films (bags). Supplies, pens, Stationery, cosmetics boxes, promotional items, nursery barrels, toys), extrusion blow molding (such as: dry powder bottles, lubricant containers, organic solvent containers, cosmetic containers, toys, etc.) application.

At present, Beijing Fengyang Plasticization Engineering & Technology Co., Ltd. has built a new plant in Daxing Development Zone Biomedical Technology Park (CBP), which has greatly improved its processing and production capabilities. The integration of technological process development and equipment self-production has been achieved, providing a solid guarantee for the industrialization of the project in the future. The successful development of starch/PVA alloy technology and complete sets of equipment of Beijing Fengyang Plasticization Engineering & Technology Co., Ltd. is still the first case in China. It not only fills a gap in China's degradable plastics industry, but also the industrialization of the project is in line with the national recycling economy. Sustainable development strategy.

Source: China Degradable Plastics Network