Research On Radiation Vulcanization Of Natural Rubber Latex With EB And Reduction Of Water Extractable Proteins In Natural Latex

Experimental researches were conducted on the radiation vulcanization of natural rubber latex (RVNRL) with low energy electron accelerator, and on reduction of water extractable proteins (WEP) in the latex. A unique under-beam facility, named as flow type reactor was designed and installed in the experiment. The process-affecting parameters such as latex circulation volume, latex concentration and beam current were evaluated by measuring the tensile strength of film of radiated latex; In the experiment of reduction of WEP in latex, Lowery method was used to explore the role of PVA, to evaluate the effectiveness of combination method (PVA+ centrifuging + film leaching). The results showed:(1) Radiation of latex with different circulation volumes makes no difference in the maximum tensile strength and production rate of vulcanized dry rubber; The larger the circulation volume, the smoother the tensile strength—radiation time curve around the maximum tensile strength. This implies that large circulation volume shall be adopted in industrial scale for favor of process control.(2) Radiation of latex with different concentration makes no significant difference in the value of maximum tensile strength; Nevertheless, the production rate of vulcanized dry rubber increases with decrease of latex concentration. This implies that RVNRL in industrial scale shall use low concentration latex.(3) The maximum tensile strength decreases with increase of beam current.(4) PVA can desorb the WEP affixed on the rubber particles. The desorbed WEP immigrates into the serum phase and afterwards is removed by the centrifuging.(5) The WEP contents in the latex film (product) can be reduced to a very low level by thecombination method, i.e. latex is centrifuged after addition of PVA, leach the film made from such latex.Based on the above results, an industrial RVNRL plant with EB shall be operated using large circulation volume low concentration latex under relative low beam current (dose rate). Radiation vulcanized natural rubber latex, treated by the combination method to remove the WEP, will bring human beings a biological safe and environment-friendly product.