Heterogeneities at the Onset of Reaction Acceleration during Bulk Polymerization of Methyl Methacrylate Investigated by Small-Angle Neutron Scattering

被引：9

作者：

Suzuki, Yasuhito ^{[2
,6
]}

Doi, Yuya ^{[1
]}

Mishima, Ryutaro ^{[2
]}

Mayumi, Koichi ^{[3
,4
,5
]}

Matsumoto, Akikazu ^{[2
,6
]}

机构：

[1] Nagoya Univ, Dept Mat Phys, Nagoya 4648603, Japan

[2] Osaka Prefecture Univ, Grad Sch Engn, Dept Appl Chem, Sakai, Osaka 5998531, Japan

[3] Univ Tokyo, Mat Innovat Res Ctr MIRC, Grad Sch Frontier Sci, Kashiwa, Chiba 2778561, Japan

[4] Univ Tokyo, Grad Sch Frontier Sci, Dept Adv Mat Sci, Kashiwa, Chiba 2778561, Japan

[5] Univ Tokyo, Inst Solid State Phys, Kashiwa, Chiba 2778581, Japan

[6] Osaka Metropolitan Univ, Grad Sch Engn, Dept Appl Chem, Sakai, Osaka 5998531, Japan

来源：

MACROMOLECULES | 2023年 / 56卷 / 10期

关键词：

FREE-RADICAL POLYMERIZATION; GLASS-TRANSITION; PHASE-SEPARATION; SUPERCOOLED LIQUIDS; EPOXY SYSTEM; DIFFUSION; SANS; POLYMERS; MMA; VITRIFICATION;

D O I：

10.1021/acs.macromol.3c00176

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

During bulk free-radical polymerization of methyl methacrylate below the glass-transition temperature of poly(methyl methacrylate), the relative fraction of monomer and polymer changes as the reaction proceeds. The liquid monomer is eventually converted to a solid glassy polymer. In other words, polymerization-induced vitrification or glass transition occurs. This process was traced by small-angle neutron scattering (SANS). The scattering profile discontinuously changes at the vicinity of vitrification. This discontinuous change was correlated with a sudden reaction acceleration known as the Trommsdorff effect. Ornstein-Zernike analysis revealed that the intensity at q = 0 (I(0)) and the correlation length of concentration fluctuation (xi) suddenly increase at the discontinuous change of the scattering profile. The obtained data implies that the increased heterogeneity (i.e., microscopic concentration fluctuation) is intimately related to the Trommsdorff effect.

引用

页码：3731 / 3738

页数：8

共 67 条

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