窄分子量分布聚四氢呋喃的合成

Preparation of Polytetrahydrofuran with Narrow Molecular Mass Distribution

以发烟硫酸-高氯酸为催化剂，通过四氢呋喃的阳离子开环聚合合成了窄分子量分布的聚四氢呋喃（PTHF）。研究了发烟硫酸和高氯酸用量、反应时间、反应温度等对PTHF分子量（Mn）及其分布（Mw／Mn）的影响。结果表明，减少发烟硫酸或增加高氯酸用量可使Mn上升；反应时间超过3h后，反应时间对Mn及Mw／Mn的影响不大；于2℃反应Mn有最大值（11760）；反应时间5h，在N2中聚合的Mw／Mn较小；低转化率（Mw／Mn小于1．2）时，通N2对Mn（4000-5500）及Mw／Mn（1．12～1．19）的影响不大。

Polytetrahydrofuran（PTHF） with narrow molecular mass distribution was prepared by cationic ring-opening polymerization of tetrahydrofuran using H2SO4 · SO3 - HClO4 system as a catalyst. The influences of H2SO4 · SO3 and HClO4 amount, polymerization time and temperature on the molecular mass（Mn） and Mw/Mn of PTHF were investigated. The results showed that the higher Mn can be obtained by decreasing H2SO4 · SO3 amount or increasing HClO4 amount; polymerization time exerted less effect over 3 h; the maxmum of Mn（ 11 760） can be reached at 2 ℃ ; Mw/Mn was smaller in N2 than in air for 5 h; Mw/Mn was 1.12 - 1.19 , Mn was 4 000 -5 500 as low conversion in air or in N2.