聚乙烯英文名称：polyethylene ，简称PE，是乙烯经聚合制得的一种热塑性树脂。在工业上，也包括乙烯与少量 α－烯烃的共聚物。聚乙烯无臭，无毒,手感似蜡,具有优良的耐低温性能(最低使用温度可达-70～-100℃),化学稳定性好,能耐大多数酸碱的侵蚀(不耐具有氧化性质的酸),常温下不溶于一般溶剂,吸水性小,电绝缘性能优良 CH2=CH2+CH2=CH2+······→—CH2—CH2—CH2—CH2······ 简写：nCH2=CH2→—[CH2—CH2]— 聚合压力大小：高压、中压、低压； 聚合实施方法：淤浆法、溶液法 、气相法； 产品密度大小：高密度、中密度、低密度、线性低密度； 产品分子量：低分子量、普通分子量、超高分子量。 Polyethylene (abbreviated PE) or polythene (IUPAC name polyethene or poly(methylene)) is the most common plastic. The annual production is approximately 80 million metric tons.[1] Its primary use is within packaging (plastic bag, plastic films, geomembranes, containers including bottles, etc.). Many kinds of polyethylene are known, but they almost always have the chemical formula (C2H4)nH2. Thus PE is usually a mixture of similar organic compound that differ in terms of the value of n.
CAS number 9002-88-4 Y KEGG C19503 Y MeSH Polyethylene Physical propertiesPolyethylene is a thermoplastic polymer consisting of long hydrocarbon chains. Depending on the crystallinity and molecular weight, a melting point and glass transition may or may not be observable. The temperature at which these occur varies strongly with the type of polyethylene. For common commercial grades of medium- and high-density polyethylene the melting point is typically in the range 120 to 130 °C (248 to 266 °F). The melting point for average, commercial, low-density polyethylene is typically 105 to 115 °C (221 to 239 °F).
Chemical propertiesMost LDPE, MDPE and HDPE grades have excellent chemical resistance, meaning that it is not attacked by strong acids or strong bases. It is also resistant to gentle oxidants and reducing agents. Polyethylene burns slowly with a blue flame having a yellow tip and gives off an odour of paraffin. The material continues burning on removal of the flame source and produces a drip.Crystalline samples do not dissolve at room temperature. Polyethylene (other than cross-linked polyethylene) usually can be dissolved at elevated temperatures in aromatic hydrocarbons such as toluene or xylene, or in chlorinated solvents such as trichloroethane or trichlorobenzene.
