The establishment of a Lewis acid-mediated selective propoxylation reaction using a specific borane catalyst enabled the synthesis of a novel class of PPG with an increased primary hydroxyl content of up to 70%. In addition, we developed a high yielding continuous process for producing the new PPG with a low amount of by-products by using tube reactors combined with film evaporators for by-product removal. Our new PPG achieves an excellent balance between reactivity and humidity resistance. As a result, it has important advantages for a broad area of polyurethane applications.
- Toru Miyajima
- Kenji Nishiyama
- Takayuki Tsuji
