The effect of process parameters, including epoxy resin composition, curing time, initiator types and levels on curing behavior were studied by taking organic silicone as toughening agent to modified epoxy resin. Curing product was analyzed by TG and DSC. The results showed that when the content of initiator 820 and T were 2%, the ratio of epoxy resin and silicone resin was 85∶15, resin system could achieve good solidification effect under the high pressure mercury lamp with 15 minutes UV curing. The tensile strength of blending resin with 15% organic silicon resin slight declines while toughness improved obviously compared with pure epoxy resin. At the same time, glass transition temperature decreased 7.5 ℃ and thermal degradation rate significantly decreased in rapid floating zone.
Table 2 Formula design (mass fraction/%) of UV curable resins
图1 树脂固化过程示意图
图2 不同树脂配比的典型温度变化曲线
图3 不同树脂配比对固化速率的影响
图4 不同树脂配比在不同光照时间下的凝胶转化率
图5 ES的质量分数对ES/CEP共混树脂力学性能的影响
Sample
S3
S10
S11
S12
S13
S14
Tg/℃
230.1
224.8
222.6
217.5
211.7
210.2
Td,5%/℃
310.6
309.4
312.1
308.3
302.4
296.5
表3 ES/CEP树脂的热性能
图6 ES/CEP树脂的DSC曲线(电子版为彩图)
图7 ES/CEP树脂的TG曲线(电子版为彩图)
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