Vacuum drying method of carbon dioxide full base degradation plastic-polypropylidene carbonate and its device

Abstract

The present invention discloses a carbon-dioxide all-base degradable plastics-polypropylidene carbonate vacuum drying method and its equipment. Said equipment includes the following several portions: spiral conveyer, transfer rotary valve, decompression transfer tank, decompression system, rotary valves with high-blocking performance, heat source and drying machine and drying unit. Said invention also provides their connection mode and the concrete operation method and steps of said vacuum drying equipment.

Description

technical field [0001] The invention relates to the technical field of drying degradable plastics, and belongs to a vacuum drying method for carbon dioxide-based degradable plastics and a device for realizing the method. The method and device are also suitable for drying other heat-sensitive, moisture-recovering materials. Background technique [0002] The research on biodegradable polymer materials began in the 1970s. Since the 1980s, countries around the world have invested a lot of manpower and material resources in the research and development of degradable polymer materials, among which degradable plastics are the fastest growing category. CO 2 All-based degradable plastic—polypropylene carbonate (PPC) is a polymer degradable plastic with good degradability. The wet material has strong photosensitivity and heat sensitivity. It is easy to decompose when exposed to light or heat before drying, and the water produced by the decomposition parts will agglomerate the plasti...

AI Technical Summary

Problems solved by technology

CO 2 All-based degradable plastic—polypropylene carbonate (PPC) is a polymer degradable plastic with good degradability. The wet material has strong photosensitivity and heat sensitivity. It is easy to decompose when exposed to light or heat before drying, and the water produced by the decomposition Parts will agglomerate the plastic particles, so CO 2 All-based degradable plastics must be dried immediately after filtration, and the drying temperature cannot exceed the material denaturation temperature; secondly, CO 2 The moisture that needs to be removed in the drying production process of all-based degradable plastics is methanol and propylene oxide, both of which are highly toxic substances, so the dryer must be airtight, and the drying tail gas cannot be discharged directly, and must be recycled by condensation; moreover , due to CO 2 All-based degradable plastic is a kind of material with high molecular weight, high viscosity, easy agglomeration, poor thermal conductivity or agglomeration degree, decomposition rate and moisture content of propylene oxide. So far, the new CO 2 Full-scale degradable plastics have not yet appeared in large-scale industrial production in China

The pilot plant jointly developed by Inner Mongolia Mengxi High-tech Materials Co., Ltd. and the Changchun Institute of Applied Chemistry, Chinese Academy of Sciences uses a vibrating fluidized bed for drying. The dried moisture cannot be recovered, and the drying requirements cannot be met, and there are even serious safety hazards and production defects.

Images