的合成微米尺寸的聚（甲基丙烯酸酯）由温度步微悬浮聚合用基于碘仿的“自由基退出洼地”效应<sup>§</sup>,Langmuir

当前位置： X-MOL 学术 › Langmuir › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

的合成微米尺寸的聚（甲基丙烯酸酯）由温度步微悬浮聚合用基于碘仿的“自由基退出洼地”效应^§
Langmuir ( IF 3.7 ) Pub Date : 2021-03-05 , DOI: 10.1021/acs.langmuir.1c00008
Chujuan Huang ₁ , Hideto Minami ₁ , Masayoshi Okubo _{1,

2}

Affiliation

以前，我们已经报道了通过微悬浮碘转移聚合（ms ITP）成功制备了微米级的聚亚甲基丙烯酸甲酯颗粒而没有亚微米级的副产物颗粒的情况，其中预期存在自由基出口抑制（RED）效应，并且相对于单体为8重量％的过氧化苯甲酰引发剂。但是，由于在水相中的聚合速度（R _p^w），与甲基丙烯酸甲酯（MMA）相比，亲水性比甲基丙烯酸甲酯（MMA）高的丙烯酸甲酯（MA）很难在相似的条件下简单地应用。从单体液滴中逸出的低聚物自由基引起的）很高，导致产生了许多亚微米级的副产物颗粒。在这项研究中，通过在MA的碘仿（ms I）的微悬浮聚合中利用两步温度过程克服了这个问题，这支持了先前论文中MMA的ms ITP中提出的机理。虽然控制分子量（M _n）和分子量分布（M _n / M _w）的限制，实现了不带副产物颗粒的微米级颗粒的制备，并通过使用ms I在满足工业需求的实际时间内实现了高转化率.MA的最佳条件是70°C（2） h，然后在80°C下加热4 h，其中含有高含量的引发剂（相对于单体8 wt％）。

"点击查看英文标题和摘要"

Synthesis of Micrometer-Sized Poly(methyl acrylate) by Temperature-Step Microsuspension Polymerization with Iodoform Based on the “Radical Exit Depression” Effect§

Previously, we have reported the successful preparation of micrometer-sized poly(methyl methacrylate) particles without submicrometer-sized byproduct particles by microsuspension iodine-transfer polymerization (ms ITP), in which the radical exit depression (RED) effect was expected, with the benzoyl peroxide initiator at 8 wt % relative to the monomer. However, it was difficult to apply it simply under a similar condition for methyl acrylate (MA), which is more hydrophilic than methyl methacrylate (MMA), because the polymerization rate in the water phase (R_p^w) arising from the oligomer radicals exiting from the monomer droplets is high, resulting in a lot of submicrometer-sized byproduct particles. In this study, the problem was overcome by utilizing a two-step temperature process in the microsuspension polymerization with iodoform (ms I) of MA, which supports the proposed mechanism in the ms ITP of MMA in the previous paper. Although the control of the molecular weight (M_n) and the molecular weight distribution (M_n/M_w) was restricted, the preparation of micrometer-sized particles without byproduct particles was realized and a high conversion was reached within a practical time that meets the demands of the industry by utilizing the ms I. The optimal conditions for MA were 70 °C for 2 h, followed by 80 °C for 4 h with a high content of initiator (8 wt % relative to a monomer).

更新日期：2021-03-16

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南