發(fā)布時間：2018-04-24 07:39

  本文選題：聚酰胺酸薄膜 + 熱處理��； 參考：《化學(xué)研究與應(yīng)用》2017年07期

【摘要】：聚酰亞胺(PI)微球制備過程中,聚酰氨酸(PAA)熱環(huán)化對PI微球性能有重要影響。為了充分了解靶丸的性能,對不同熱處理溫度下的PAA薄膜光學(xué)性質(zhì)和力學(xué)性能進(jìn)行了分析。實驗表明:隨著熱處理溫度的增加,PAA薄膜光學(xué)性質(zhì)發(fā)生明顯變化,紫外透過光譜曲線截止波長也隨之變化。溫度波動在0~250℃時紅移,250℃達(dá)到最大值,250~350℃出現(xiàn)藍(lán)移現(xiàn)象,350℃達(dá)最大值。同時光學(xué)帶隙數(shù)據(jù)證明了波長大于600nm時,光波能量小于光學(xué)帶隙值,投射光不能被吸收,故透過率達(dá)90%以上。同時小于400nm光波能量大于光學(xué)帶隙值,投射光全部被吸收,透過率為0。隨著溫度增加薄膜的楊氏模量和硬度出現(xiàn)先減小后增加的趨勢,其數(shù)值由9.16和0.32GPa減小到4.98和0.27GPa,再增加到5.99和0.31GPa。以上數(shù)據(jù)都與薄膜的結(jié)構(gòu)變化有關(guān),隨著溫度增加,PAA逐漸轉(zhuǎn)化為PI,250℃時反應(yīng)較為劇烈,此時轉(zhuǎn)化率較高,分子內(nèi)COOH和CONH脫水,形成C-N鍵。250℃以后少量PAA繼續(xù)轉(zhuǎn)化為PI,同時水分蒸發(fā),300℃以上大部分PAA薄膜轉(zhuǎn)化為PI故性質(zhì)較為穩(wěn)定,350℃和300℃變化較小。
[Abstract]:During the preparation of polyimide (Pi) microspheres, the thermal cyclization of PAA has an important effect on the properties of Pi microspheres. In order to fully understand the properties of the target, the optical and mechanical properties of PAA films at different heat treatment temperatures were analyzed. The experimental results show that the optical properties of PAA thin films change obviously with the increase of heat treatment temperature, and the cut-off wavelength of UV transmission spectrum also changes. When the temperature fluctuates at 0 ~ 250 鈩，

本文編號：1795743