Low unsaturation polyoxyalkylene polyether polyols

摘要

There is now provided an isocyanate reactive polyoxyalkylene polyether polymer having a structure as follows: the nucleus of an initiator compound, an internal block of oxypropylene groups, and a second block of oxyalkylene groups; the internal block of oxypropylene groups being between the nucleus of the initiator and the second block, the second block containing at least some oxyalkylene groups derived from at least a C4 or higher alkylene oxide. This structure allows one to make a polyether polymer having a low degree of unsaturation, adjust the degree of hydrophobicity to a wide range of values, and may be simply manufactured without depending upon the use of exotic catalysts. The amount of the internal block of oxypropylene groups is advantageously from 25 weight percent to 80 weight percent based on the weight of all oxyalkylene groups and initiator compound. The amount of the second block containing a C4 or higher alkylene oxide should be effective to reduce the unsaturation of the polyether polyol to 0.06 meq KOH/g of polyol or less.