协同二元有机催化环开口聚合,用于聚氧的精密合成
Hiroshi Okamoto1, Atsushi Sogabe1, Satoshi Honda2
1MIRAI Technology Institute, Shiseido Co. Ltd, 1-2-11 Takashima, Nishi-ku, Yokohama, Kanagawa, 220-0011, Japan.
Communications chemistry
|March 22, 2024
概括
二元有机催化环开放聚合 (BOROP) 能够使用有机基和 (thio) 尿素精确合成聚二甲基酸盐 (PDMS). 这种方法克服了聚氧合成的挑战,产生了具有卓越机械性能的高质量弹性体.
科学领域:
- 聚合物化学 聚合物化学
- 机体催化剂是有机催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 有机催化环开放聚合 (ROP) 提供了对聚合物合成的控制,但在聚烯生产方面面临挑战.
- 现有的方法与极性不匹配以及循环素聚合过程中的转乙烯化等副作用作斗争.
- 在聚合物科学中,实现具有可控架构的精确定义的聚氧仍然是一个重大障碍.
研究的目的:
- 开发一种精确的合成方法,用于polysiloxanes使用一个新的二元器官催化系统.
- 克服当前有机催化 ROP 对于诸如六甲基环三素 (D3) 等非极性单体的局限性.
- 研究有机基和 (thio) 尿素在控制聚合过程中的协同作用.
主要方法:
- 采用二元有机催化环开放聚合 (BOROP) 方法对六甲基环三素 (D3).
- 作为催化剂,利用有机基,特别是三二环烯 (TBD) 和1,8-bis (TMGN),作为催化剂.
- 纳入 (thio) 尿素作为辅助催化剂,调节聚合活性和选择性.
主要成果:
- 使用TBD和 (thio) ureas.使用狭窄分散度 (Mw/Mn <1.1) 的生成的聚二甲基烯酸盐 (PDMS).
- 证明单独的TMGN是无活性的,但与尿素的协同作用使得D3.3的控制BOROP能够得到控制.
- 产生的PDMS弹性体具有统一的网络结构,增强的伸展性和优良的机械性能.
结论:
- 开发的二元有机催化系统 (BOROP) 有效地控制了D3.3的环开放聚合.
- 催化剂和共催化剂之间的协同激活-失活平衡是实现高质量的PDMS的关键.
- 这种方法为合成具有量身定制性质的先进聚氧材料提供了一条途径.
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