비의류제품

Low-Molecular Weight Epoxy-Bisphenol Resins.

  • 출판일1998.12
  • 저자
  • 서지사항
  • 등록일 2016.11.02
  • 조회수 462
Researchers used a two step procedure to prepare title resins. The procedure involved adding bisphenol A to epichlorohydrin over the catalysts chlorocholine chloride and Ca(0H)(2) at 55-65 degrees centigrade until the phenol's OH was converted at > 90 percent and dehydrochlorinating byproducts and beta-chlorohydrin by driving off the excess of epichlorohydrin at 115-135 degrees centigrade per 20 millimeters Hg, dissolving the intermediates in MEK and dehydrochlorinating at 50-55 degrees centigrade with aqueous 20 percent NaOH, or with aqueous 40 percent NaOH in the unconverted epichlorohydrin solution with, or without some i-PrOH added. The epoxide equivalents and viscosities at 25 degrees centigrade of the resins were 176-185 grams per mol and 6,900-11,400 megapascals, respectively, and suggested low contents of higher oligomers and alpha-glycol groups. 14 refs.
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