Download or read book GB T 12008 3 1989 Translated English of Chinese Standard GBT 12008 3 1989 GB T12008 3 1989 GBT12008 3 1989 written by https://www.chinesestandard.net and published by https://www.chinesestandard.net. This book was released on 2020-09-26 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: This standard specifies the method for determining the hydroxyl number of polyether polyols by the phthalic anhydride esterification method. This standard applies to the determination of the hydroxyl number of polyether polyols for polyurethane foams which are made by the ring-opening polymerization of polyols, ethylene oxide and propylene oxide under the action of a catalyst.

Download or read book GB T 12008 3 2009 Translated English of Chinese Standard GBT 12008 3 2009 GB T12008 3 2009 GBT12008 3 2009 written by https://www.chinesestandard.net and published by https://www.chinesestandard.net. This book was released on 2020-10-16 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Part of GB/T 12008 specifies two methods for the determination of the hydroxyl value of polyether polyols. Method A is phthalic anhydride method. It is recommended for polyether polyols, polymer polyols and polyols with ammonia as initiator. But for polyols with steric hindrance, the result shall be lower. If corrective measures can be taken, other polyols can also apply this method.