迈入二十一世纪之际,住宅建筑和基础建设是带动我国国民经济走向新高潮的支柱产业。新型建筑材料,包括各种建筑用塑料,正面临着大发展的历史机遇。早于十九世纪,人类已发现了聚氯乙烯(PVC)的存在,被工业化生产及付诸实际应用已有七十年的发展历史。美国近几年来UPVC管的产量保持逐年增长,由1994年的209.1万吨发展到 As we enter the 21st century, residential buildings and infrastructure are the pillar industries that will propel our national economy to a new upsurge. New building materials, including all kinds of plastic used in construction, are facing the historic opportunity of great development. As early as the 19th century, human beings have discovered the existence of polyvinyl chloride (PVC), which has been industrially produced and put into practical use for 70 years. The production of UPVC pipe in the United States has been increasing year by year in recent years from 2,091,000 tons in 1994