甲醇引發UV輻射聚甲基丙烯酸酯之裂縫癒合

Methanol-Induced Crack Healing in UV-Irradiated Poly(methyl methacrylate)

許瀚仁(Han-Ren Hsu)

指導教授 ： 李三保

國立清華大學/工學院/材料科學工程學系/碩士(2014年)

https://doi.org/10.6843/NTHU.2014.00371

摘要

本論文嘗試利用兩種方式來探討紫外光對於聚甲基丙烯酸酯的影響，(1)20度到35度的甲醇質傳以及(2)拉伸試片裂縫癒合
當聚甲基丙烯酸酯受到300奈米以下波段的紫外光照射，會產生鏈射解，因而大大影響聚甲基丙烯酸酯的機械性質。
質傳方面可以利用Harmon model來分析受紫外光的影響。
經過紫外光照射後的試片，經浸泡甲醇也可以產生裂縫復原的現象，藉以討論其性質變化。

關鍵字

甲醇 ； 裂縫癒合 ； 輻射 ； 聚甲基丙烯酸酯

並列摘要

The effect of UV irradiation on the methanol transport in poly(methyl methacrylate) has been studied at temperatures from 20oC to 35oC. It was found that photodegradation of PMMA irradiated by UV of wavelength less than 300 nm includes main-chain scission and side-chain scission, which decreases mechanical properties of PMMA. The irradiated PMMA showed faster mass transportation at higher temperature and greater dosage. Harmon`s model is used to fit the transport curve, the activation energies for diffusion (ED) and relaxation processes (EV) were calculated from the Arrhenius plots of D and v.
Cracked PMMA sample can be healed by methanol treatment. Crack healing occurs because the effective glass transition temperature treatd by methanol treatment is lower than the operating temperature. Such treatment could heal the crack and repair strength of PMMA. After UV irradiation, crack healing curve changed. We could study how the crack heals under the influence of UV irradiation.

並列關鍵字

PMMA ； UV ； crack healing ； methanol

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