纤维素内塑化材料的制备及性能

Internal Plasticization of Cellulose and Property Characterization

用微波辐射法快速合成了纤维素长链脂肪酸酯。通过对改性产物的红外光谱及核磁共振光谱表征,证明柔性脂肪酸酯基引入了纤维素骨架。对溶液浇铸法所得薄膜材料的耐水性、玻璃化温度(Tg)、热稳定性、拉伸强度及断裂伸长率进行了分析测定,探讨了取代度对材料性能的影响。结果表明,改性材料表面具有良好的疏水性质,其接触角均在90°左右;由于柔性酯基链的引入,所制备的纤维素改性薄膜具有一定的内塑化性能。取代度为1.8的样品,其Tg为153℃,起始分解温度为198℃,断裂伸长率为50%,拉伸强度约为12 MPa,与线性低密度聚乙烯相当。

This paper demonstrated the esterification of cellulose with long chain carboxylic acid in a homogeneous phase by microwave irradiation. Partially derivatized celluloses were characterized with the aid of FT-IR and NMR measurements. The influences of the degrees of substitution （DS） on the properties of films by casting were studied. The results Show that the contact angle of all products is nearly 90°, decomposition onset at 198 ℃, Tg = 153 ℃, elongation = 50%, and the tensile strength of the film with DS = 1.8 （ - 12 MPa） is equivalent to these obtained for linear low-density polyethylene.