Research The Alcoholysis Of Waste Polyurethane Material

Polyurethane is the macromolecular compounds with repeating carbamate groups in the main chain. It is made of organic isocyanate or isocyanate and polyol in addition polymerization. Polyurethane products include flexible foam, semi-rigid foam and rigid foam, elastomer, paint, coating, adhesive, sealant, synthetic leather coating resin, elastic fiber, and widely used in automobile manufacturing, refrigerator manufacturing, transportation, civil in construction, footwear, synthetic leather, fabric, machinery and electronics, petrochemical, mining machinery, aviation, medical, agriculture and many other fields.Consumption of polyurethane products in China increased every year, it will be difficult to degrade so large quantities of polyurethane waste which will be exit in the environment for decades or even hundreds of years, and it must take serious damage to the environment. Environmental awareness is gradually enhanced, eliminating white pollution, achieving full utilization of resources to ensure sustainable economic and social development become an urgent need to solve the problem of recycling waste polyurethane.In this paper, the article first made a brief overview of technologies and development trends about recycling and the degradation of waste polyurethane material. And the article focused on the principles and methods of recycling waste polyurethane waste in glycolysis to polyurethane elastomer, flexible foam and rigid foam.In this paper, the article studied waste polyurethane elastomer, waste flexible polyurethane foam and waste rigid polyurethane foam, and recycled polyol from them by glycolysis. By changing the type of glycolysis agent, such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol; changing the glycolysis temperature,120C-200C; changing the glycolysis time,2h-15h; changing the ratio of polyurethane and glycolysis agent,1:0.5,1:1,1:2,1:3; adding assistant glycolysis agent, such as diethanolamine, triethanolamine, the article studied systematically the glycolysis of waste polyurethane materials, separated the glycolysis product, and analysis the polyol in the upper layer, filtered out the optimal conditions by contrasting with the glycolysis rate.This article uses Fourier transform infrared spectroscopy to identify the type of polyol, such as polyester polyol, polyether polyol; the type of isocyanate, such as MDI, TDI, and analyze the glycolysis product in qualitative; using gel permeation chromatography toanalyze the molecular weight of the glycolysis products, and analyze the OH value and viscosity to study the effect of glycolysis; using differential scanning calorimetric instrument to analyze the thermal changes of waste polyurethane, identify their glass transition temperature and softening point.