Application And Research Of Natural Rubber Latex By Biological Modification

Natural rubber latex is comes from milk secretion of hevea with process, as a renewable natural resource, it is widely used in medical areas, health and family planning, but there are still some physical and mechanical problems of natural rubber latex products, and they can even cause allergic reaction easily in some people, the main allergic factor is water-soluble proteins in the natural rubber latex. However, the excellent properties of natural rubber latex is cannot be replaced by many other materials, so how to reduce the allergy of natural rubber latex and improve the mechanical properties and surface properties that becomes the hot issue in the world.Presently to achieve the goal of reducing allergy of natural rubber latex by removing the proteins of latex at home and abroad, which is divided into the treating processes of raw materials and latex products, but it also has some problems in the effectiveness, production and environmental protection. With the allergy of proteins, we introduced the environmental-friendly, safe and reliable transglutaminase(MTGase). Due to its unique capacity, we used it to form irreversible crosslinking between proteins in the latex. Furthermore by adding sodium glutamate and lysine which could change the environmental factors of crosslingking reation and promote the crosslinking reaction of proteins in the latex, further reduced the content of water-soluble proteins and made hypoallergenic natural rubber latex. With some physical problems of latex films such as compactness, solvent resistance and so on, we used biological gums to improve the properties of latex films and to make high-performance products.We verified the crosslinking reaction of proteins in the natural rubber latex by SDS-PAGE, IR spectrums of structure characterization, particle size distribution of emulsion and so on. In the experiment of adding lysine and sodium glutamate, we combined single-factor test and orthogonal experimental to get the best conditions of crosslinking reaction with proteins. The properties of the modified films with transglutaminase or biological gums were identified by mechanical properties testing, analysis of surface morphology, solvent resistance, cytotoxicity experiment and so on.The results showed that:transglutaminase really catalysed crosslinking reaction of proteins in the natural rubber latex. After adding the lysine and sodium glutamate, the content of water-soluble proteins had been further reduced in the natural rubber latex, the cytotoxicity and mechanical properties of latex films were improved. And from the study of the films treated by biological gums, we found that xanthan gum and pullulan could better improve the mechanical properties, solvent resistance, compactness and so on.