PC-聚碳酸酯注塑常见缺陷分析及解决方法（Common defect analysis and solution of pc-polycarbonate injection molding）.doc

PC-聚碳酸酯注塑常见缺陷分析及解决方法（Common defect analysis and solution of pc-polycarbonate injection molding） Polycarbonate (PC) is a kind of excellent engineering plastic, not only high transparency, excellent impact toughness, and creep resistance, non-toxic, using a wide temperature range and good dimensional stability, good electrical insulation, good weather resistance, so they are widely used in instruments and meters, lighting appliances, electrical and electronic equipment, household appliances, packaging and other industries. In addition, with the rapid development of polymer materials, the new variety of modified varieties has been continuously developed, which has greatly expanded its application field. At the same time, its processing technology is getting more and more attention. PC is the main chain of the molecular structure containing benzene, isopropyl, vinegar key linear polymers, this structure makes it have both rigid and flexible, and good high temperature resistant ability, but at the same time there is a high melt viscosity of the resin and is sensitive to water shortage, bring certain difficulty sichuan injection molding processing. Its processing characteristics is no obvious melting point, in the normal processing temperature is 230 a high melt viscosity of 320 ℃ scope, the sensitivity of viscosity to shear rate of small and large sensitive to temperature, similar to Newton fluid behavior; Sensitive to moisture, the resin is easy to hydrolyze under high temperature; The products are easy to produce internal stress and so on. Thus, the PC is a more difficult plastic. So in the actual production process, we have more problems. Now several common product defects are analyzed and discussed. One, the product changes color, appears to become black, yellow grain and black dot Contrast, PC has good heat resistance, normally when processing of PC material, its melting temperature can be set in 240 - a - 300 ℃, even if long time stay, general wont break down. Why