秸秆基高强度透明纤维素薄膜

From Cellulose in Straw to Transparent High-strength Films

以农业废弃产物秸秆皮作为原料,通过简单热压的方法提纯纤维素,制备了不同厚度的微纤薄膜(SCfilms),将环氧树脂加压铸入微纤薄膜获得了纤维素-环氧树脂复合薄膜(SC-Epfilms).采用扫描电子显微镜、傅里叶变换红外光谱仪、紫外-可见分光光度计对SC与SC-Ep薄膜分别进行表征,并对其力学性能、防水性、热稳定性、有机溶剂稳定性及阻隔性能进行测试.结果表明,最佳复合薄膜(SC_(4)-Ep1)呈现了优异的透光性(最高透过率可达87%)、高力学强度(拉伸应力可达83.4 MPa,杨氏模量为5.41 GPa),远高于文献中以及市场上同类型的塑料薄膜材料.此外,从SC_(4)薄膜到SC_(4)-Ep_(1)薄膜,接触角提高至98.9°,水蒸气透过率显著降低了75.12%,表现出优异的阻隔性能.SC_(4)-Ep_(1)复合薄膜在水中以及多种有机溶剂中表现出极强的稳定性.本工作为制备复合生物基薄膜以及生物基塑料产品提供了新的思路.

Petroleum-based plastics can cause serious environmental problems such as“microplastics”,and common biobased plastics are generally expensive and produced by complex processes.It is thus urgent to develop new biobased materials that are inexpensive,simple to prepare,and possess superior properties.In this work,we used agricultural waste straw bark as raw material,and fabricated microfiber films(SC films)with varied thicknesses by simple hot pressing.Then,cellulose-epoxy films(SC-Ep films)were obtained by pressure casting of epoxy resin into microfiber films.Scanning electron microscopy(SEM),Fourier transform infrared spectrometer(FTIR),and ultraviolet-visible spectrophotometer(UV-Vis)were used to characterize SC and composite SC_(4)-Ep_(1) films.In addition,their mechanical properties,water resistance,thermal stability,organic solvent stability,and barrier property were investigated.The results showed that the optimal film(SC_(4)-Ep_(1) films)presented a transmittance as high as 87% and outstanding mechanical strength(tensile stress up to 83.4%,Young’s modulus 5.41 GPa)that is much higher than those of similar types plastic materials in the literature as well as in the market.In addition,the water vapor transmission rate was significantly reduced by 75.12% from (SC_(4) films)to SC_(4)-Ep_(1) films composite film,exhibiting superior barrier property.SC_(4)-Ep_(1) films also displayed excellent stability in water and various organic solvents.This work provides a new approach to the preparation of composite bio-based films as well as bioplastic products.