论文摘要翻译 材料方向200字左右~求高手

论文摘要翻译 材料方向200字左右~求高手
翻译原则：第三人称、过去式、被动语态

翻译内容
摘 要
PVA薄膜是一种用途广泛的水溶性高分子材料,具有良好的透明性和韧性,阻隔性和保香性能极佳,是一种很有发展前景的绿色包装材料,但由于PVA分子中含有大量的羟基,易与水分子中的羟基形成氢键,导致耐水性能很差,应用受到了很大的限制.本课题分析目前改进聚乙烯醇耐水性的研究成果中的优缺点,最后选用了尿素和硼酸作为改性剂来提高聚乙烯醇薄膜的耐水性能,通过实验数据对比这两种改性剂的改性效果.在本次课题的实验中,分别使用了不同用量的尿素和硼酸作为改性剂,用流延法制备改性薄膜,用测试薄膜溶解率和溶胀率的方法对薄膜耐水性进行测试,并测试了改性薄膜的拉伸强度、断裂伸长率等力学性能,结果表明尿素作为改性剂改善聚乙烯醇薄膜耐水性的效果优于硼酸,尿素用量为总量的0.8%时,改性效果最好,另外对改性薄膜力学性能的测试结果表明,改性剂的种类和用量对改性薄膜的力学性能有影响,改性薄膜的力学性能随着耐水性能的增大有上升的趋势.
关键词：PVA；耐水性；尿素；硼酸

PVA film is a use in a wide range of water-soluble polymer material with good transparency and toughness, and block, and the Hong Kong excellent performance and is a very promising green packing materials, but the PVA elements contain a significant amount of hydroxy, and it is easy to and water molecules in a hydroxy hydrogen to water-resistant performance is poor, the application was subject to considerable restrictions. The task analysis of the current improved polyethylene glycol and water, the research results of the advantages and disadvantages, and finally the urea and boric acid as a modifier to improve polyethylene glycol film of water-resistant performance, through experimental data comparison of the two Agent modified the modified results. At the time of the topic in the lab, use a different usage of the urea and boric acid as a modifier, the flow rule for a modified film, the test film dissolved and soluble inflation rate in the film water resistant to test, and test the modified membrane of the tensile strength, Elongation to break, and mechanics performance, the results showed that urea as modified, improved polyethylene glycol film resistant to water the results better than boric acid, urea usage for total of 0.8 per cent, living modified organisms best results, as well as the modified membrane mechanics performance test results indicate that living modified organisms, the types and usage of the modified membrane of the mechanics performance impact, modified membrane of mechanics performance with water-resistant performance of the increase has been on the rise.
Key words: PVA; Water Resistant; urea; boric acid