Chemical Degradation Of Waste Polyurethane Elastomers

Polyurethane materials are widely used in mechanical and electrical industry, aerospace industry, auto industry, civil engineering, textile industry and other fields for theirs excellent performances on mechanical properties, flexibility, abrasion resistance and chemical resistance. And with the extensive application of polyurethane materials in above-mentioned areas, there are more and more polyurethane wastes need to be treated. The treatment of polymer wasters has received more and more attention. Most of polyurethane materials belong to thermosetting polymers, which were treated by the major methods including landfill and incineration .Those methods not only waste a large number of chemical raw materials, but also result in air pollution of land. Therefore, how to recycle and reuse polyurethane waste effectively has become an issue.In this paper, the article first made a brief overview of the technologies and development trends about recycling and degradation of polyurethane wastes. And the article focused on the principles and technology of chemical degradation. Then, a degradation method and experiment was investigated to treat polyurethane elastomer waste.In this paper, glycolysis has been investigated to degrade the thermosetting polyurethane elastomer waste with 1,4 - butanediol and triethanolamine as alcoholysis agents. Polymer polyol, which is recyclable material, was separated from degradation products. Then, the effects of the ratio of 1,4 - butanediol, triethanolamine and polyurethane elastomer waste on viscosity and hydroxyl of degradation products were researched . Through the characterization and analysis of degradation products, mass ratio of reactants was determined.In this paper, polyurethane elastomer waste was degraded in HAAKE torque rheometer with tributyl phosphat as the degradation agent, and the degradation product was thermoplastic polyurethane elastomer. The effects of reaction temperature and the ratio of polyurethane elastomer waste to tributyl phosphat on the degradation reaction were researched. The rheological behavior of the process of thermal degradation was discussed by the extraction and gel permeation chromatography testing of the degradation products. Thermoplastic polyurethane elastomer with different degradation state could be obtained by control degradation degree, using degradation time. Then, the thermal degradation respectively with kaolin, heavy calcium carbonate and talc powder were researched and filler-filled thermoplastic polyurethane elastomer composite materials has been obtained directly. At last, the surface morphology of tensile cross-section of composite materials was observed by scanning electron microscopy and the mechanical properties of composite materials has been tested and analyzed.