CAJ | 학술논문

为了实现木质纤维原料中主要组分的高效利用,且获得低降解的乙酰化析出产物,在较为温和的反应条件下,对胡桑枝条木粉进行了两步乙酰化反应的研究,并与高温条件下乙酰化以及三氟乙酸为催化剂乙酰化两种方法分别进行了对比。6g胡桑木粉原料,浓硫酸、乙酸酐、冰乙酸与木粉原料质量比分别为1：8、25：2和10：1,在80℃下反应3 h,得到第一步乙酰化产物(AS1)；第一步乙酰化反应残渣在90℃下反应4 h,浓硫酸、乙酸酐、冰乙酸与木粉原料质量比分别为1：20、15：2和15：2得到第二步乙酰化产物(AS2)。实验结果表明：乙酰化析出产物得率为112.60%,初始降解温度为175℃,其二氯甲烷溶液特性黏度为71.09 mL/g,均优于高温条件下乙酰化和三氟乙酸为催化剂乙酰化所得的改性产物。产物的FT-IR分析表明乙酰基成功接入。 TG分析显示产物初始降解温度为175℃,DSC分析显示产物在160℃处出现玻璃化转变,具有较好的热稳定性和一定的热塑性。
위료실현목질섬유원료중주요조분적고효이용,차획득저강해적을선화석출산물,재교위온화적반응조건하,대호상지조목분진행료량보을선화반응적연구,병여고온조건하을선화이급삼불을산위최화제을선화량충방법분별진행료대비。6g호상목분원료,농류산、을산항、빙을산여목분원료질량비분별위1：8、25：2화10：1,재80℃하반응3 h,득도제일보을선화산물(AS1)；제일보을선화반응잔사재90℃하반응4 h,농류산、을산항、빙을산여목분원료질량비분별위1：20、15：2화15：2득도제이보을선화산물(AS2)。실험결과표명：을선화석출산물득솔위112.60%,초시강해온도위175℃,기이록갑완용액특성점도위71.09 mL/g,균우우고온조건하을선화화삼불을산위최화제을선화소득적개성산물。산물적FT-IR분석표명을선기성공접입。 TG분석현시산물초시강해온도위175℃,DSC분석현시산물재160℃처출현파리화전변,구유교호적열은정성화일정적열소성。
For utilizing the main components of the mulberry branch effectively and obtaining acetylated products with low degraded degree, the method of two-step acetylation was carried out under the relatively mild condition. At the first step, the acetylated product( AS1 ) was obtained after 3 h at 80 ℃, and the quality ratio of sulfuric acid, acetic anhydride and acetic acid with the raw material was 1:8, 25:2 and 10:1, respectively. At the second step, the acetylated product( AS2 ) was obtained after 4 h at 90 ℃, and the quality ratio like the above was 1:20, 15:2 and 15:2. The results showed that the yield of the acetylated product by two-step was 112. 60%, the intrinsic viscosity was 71. 09 mL/g and its initial degradation temperature was 175 ℃. They were all superior to those by the trifluoroacetic-acid method and high-temperature method. Fourier transform infrared spectroscopy ( FT-IR ) of the product by two-step acetylated showed that the signals corresponding to acetyl were identified. Thermogravimetric analysis ( TGA ) showed that the product started to degrade at 175 ℃ and differential scanning calorimeter ( DSC) results revealed that the glass transition point was 160℃.