Synthesis and Characterization of Low Volatile Content Polyurethane Dispersion from Depolymerised Polyethylene Terphthalate

In the past few decades, governments and international agencies have been placing more emphasis on the improvement of production technique, working conditions and reduction of the toxic emission to the atmosphere. In this context aqueous polyurethane dispersion was synthesized from depolymerised polyethylene terphthalate (PET) waste. 1,4-Butanediol was used in PET depolymerisation. Polyurethane dispersion films were characterized using differential scanning calorimeter, Fourier transform infrared spectroscopy, gel permeable chromatography, etc. Incorporation of PET waste in polyurethane dispersion was an added advantage in waste management and produced better quality polyurethane dispersion.     

聚乙烯管热熔焊机技术现状分析

基于国内常见品牌聚乙烯管热熔焊机的性能检测结果,详尽地从焊机主要机械部件性能、温度与压力等焊接参数的控制,以及全自动热熔焊机的监控性能与焊口信息记录情况等方面分析了热熔焊机的技术现状。分析表明,热熔焊机普遍存在若干不容忽视的质量问题,其中许多为焊机质量不能满足国家标准要求。最后提出了提高焊机技术水平的措施。