| China is a large agricultural country, agriculture is the pillar industry of our country has been concern and attention, as an important means of production of plastic sheeting, play a decisive role in agricultural production. In recent years," Three rural issues " is always the priority among priorities, the government departments to further increase the strong agricultural Huinong policy kulaks, struggling to seize a good harvest in agriculture. This provides opportunities and good development environment for the agricultural industry. But at the same time, China’s film industry into the threshold low, more than nine of plastic sheeting enterprises are small enterprises lack of technology and investment, which leads to flooding the market mostly workshop production of low-grade plastic sheeting, high-grade plastic sheeting and low occupancy rate. At present, in the high, low-grade plastic sheeting accounted for about2%, less than40%and greater than60%, and the proportion of foreign developed countries is20%,50%,30%. The structure of product market in the long-term development is not balanced, not only caused great waste of resources, but also restricting enterprise for the development of new technology, new product. Under this situation, film industry to the healthy development, it must be the farmers demand at the same time improve functional agricultural film in harmless agricultural products, realize the long ageing resistance function. With plastic film as an example, especially for a Yunnan as the representative of the plateau region, conditions of geography environment special speed film aging, replacement frequency short time to reduce farmers costs, and strong ultraviolet radiation has a serious impact on the quality and the quality of crops. So we are longing for a resin model of high performance, high value-added appear.In this study, from the ordinary film materials, production process, performance as the foundation, through the comparison of the performance of several different film production base material, combined with the actual production requirements, is chosen to get the linear low density polyethylene (LLDPE), low density polyethylene (LDPE) and metal linear low density polyethylene (m-LLDPE) blend of three system is the main choice for producing high-quality films with; study on the use of inorganic nanoparticles unique toughening and UV reflection, was modified to achieve anti plateau strong ultraviolet radiation, weathering by adding nano silica on the mechanical properties, the effective realization of the common films and significantly improve the anti ultraviolet aging properties, and adding nano silica in monolayer in the amount of3%best; and the use of silane coupling agent on the nanoparticles were dispersed, made functional masterbatch and film base material blend membrane, finally get the nano modified film, the method is simple, cost-effective. Get after test adding nano silica, level of mechanical properties of film has been greatly improved, and the national standard (GB4455-2006) to compare, elongation, tensile strength and tear strength on the right are respectively169%,162%and108%improved in different degree, and has obvious barrier of210nm within350nm UV the effect of weathering performance, it is much better than that of ordinary film, service life of up to3-4years, fully meet the requirements of agricultural use in Plateau area; in addition, nanometer silicon dioxide modified film can also be fully recycling production, help to promote the use of plastic sheeting and recovery, favorable for repeated use of membrane, has environmental significance. |
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