蓝藻基生物降解共混膜的力学性能

Mechanical Properties of Cyanobacteria-Based Biodegradable Blend Films

以聚乙烯醇(PVA)和水华蓝藻为主要原料,通过溶液铺膜法制备了蓝藻/PVA共混膜,采用万能试验机,研究了不同助剂对蓝藻/PVA共混膜力学性能的影响。结果表明,蓝藻的添加显著降低了共混膜的力学性能。当添加比例为PVA的1/2时,膜的拉伸强度和断裂伸长率分别比无藻处理下降了65.89%和79.57%。甘油、尿素显著提升了蓝藻/PVA共混膜的断裂伸长率,当添加比例为蓝藻的1/2时,分别能使共混膜的断裂伸长率提高73.20倍和62.02倍。虽然柠檬酸、硅烷偶联剂能够提升蓝藻/PVA共混膜的拉伸强度,但只能在低剂量时促进断裂伸长率的小幅提高,当柠檬酸添加比例为蓝藻的1/40时,膜的断裂伸长率能提高4.41倍,而当硅烷偶联剂添加比例为蓝藻的1/20时,膜的断裂伸长率能提高1.49倍。尿素与甘油复合增塑,更有利于提升共混膜的断裂伸长率。硅烷偶联剂与甘油复合增塑,更有利于提升共混膜的拉伸强度。

Cyanobacteria/PVA blend films were prepared by solution casting with polyvinyl alcohol(PVA)and blooming cyanobacteria as main raw materials.The effects of different additives on the mechanical properties of cyanobacteria/PVA blend films were got by universal testing machine.The results indicated that the mechanical properties of the blend films were significantly worse by adding cyanobacteria.When the ratio of cyanobacteria to PVA was 1/2,the breaking elongation and tensile strength of the films were decreased by 65.89%and 79.57%,respectively,compared to algae-free treatment.Breakingelongation of the blend films could be significantly improved by adding glycerol or urea alone.When the proportion of glycerol/urea to cyanobacteria was 1/2,the breaking elongation of the blend films could be increased by 73.20 times and 62.02 times,respectively.The tensile strength of cyanobacteria/PVA blend film could be improved by citric acid or silane coupling agent alone,but the breaking elongation could be slightly increased only at low dosage.When the ratio of citric acid to cyanobacteria was 1/40,the breaking elongation at of the blend films could be increased by 4.41 times.When the ratio of silane coupling agent to cyanobacteria was 1/20,the breaking elongation of the films could be increased by 1.49 times.During the joint plasticization with glycerol,the use of urea was more beneficial to improve the breaking elongation of the films,while the use of silane coupling agent was more helpful to improve the tensile strength of the films.