壳聚糖／聚乙烯醇梯度材料的制备及表征

采用微波技术,以壳聚糖(Cs)和聚乙烯醇(PVA)为组分,戊二醛为交联剂,制备出Cs(或PVA)质量分数沿厚度方向由高(低)到低(高)渐变的梯度材料。将该梯度材料沿厚度方向进行切片,通过红外光谱、元素分析法对各层组成和结构进行了表征;并研究厂各层的吸水性能和机械性能。结果表明:在该梯度材料中,Cs质量分数、溶胀率、拉伸强度、断裂伸长率以及拉伸模量沿厚度方向呈现渐变。其中Cs质量分数的变化范围为81%～17%,溶胀率为54%～350%,拉伸强度为65.4～33.2 MPa,断裂伸长率为28.6%～81.1%,拉伸模量为4.75～1.17 GPa。

Preparation and Characterization of Chitosan/Polyvinyl Alcohol Gradient Material

With chitosan (Cs) and polyvinyl alcohol (PVA) as raw materials,pentadial as crosslinker,a polymeric gradient material was prepared by means of microwave technique,in which the mass fractions of the two components Cs and PVA were changed from high (low) to low (high) gradually along the thickness direction.Vari- ous layers of the gradient Cs/PVA cut from the surface to the bottom of the sample were measured by means of Fourier transform infrared spectrometer (FTIR) and elemental analysis.The swelling ratio (SR) in water and the mechanical properties of the layers in Cs/PVA gradient material were also investigated.The results indicated the mass fraction of either component,SR,tensile strength,elongation at break and tensile modulus showed a gradual change along the thickness direction.From the top to the bottom,the change range of the mass fraction of Cs was from 81% to 17%,that of SR was from 54% to 350%,that of the tensile strength was from 65.4 MPa to 33.2 MPa,that of elongation at breaking was from 26.8 % to 81.1%,and that of the tensile modulus was from 4.75 GPa to 1.17 GPa.