Preparation method of polyisoprene rubber latex

Abstract

The invention discloses a preparation method of polyisoprene rubber latex. In an emulsifier system, an anionic emulsifier is one or more of sodium dodecyl benzene sulfonate and isomeric alcohol ether carboxylate; a non-ionic emulsifier is one or more of Tween 80, Peregal O-20 and cetylphenol polyoxyethylene ether, the total use level of the emulsifiers is 10-20% of dry glue by mass, and a co-emulsifier accounts for below 20% of the dry glue by mass. Rubber is dissolved by using saturated alkane to prepare a rubber solution, wherein the rubber concentration in the rubber solution is 9.0-12.0% with the oil-water ratio of 1.0-1.5. An O / W emulsion is prepared by adopting an emulsification way of premixing and shearing and emulsifying. A hydrocarbon solvent is removed by way of reduced pressure distillation and membrane distillation to obtain diluted latex with the residual volume of the hydrocarbon solvent less than 80ppm. In the reduced pressure distillation process, physical defoaming is realized by adopting a nitrogen flow or an air flow and the molecular weight loss of polymers in the latex is less than 3.0%. The diluted latex is centrifugalized and concentrated by adopting a high-speed centrifugal machine to respectively obtain concentrated latex and whey. Whey is mixed with a newly prepared emulsifier solution, so that the emulsifier in whey is reused. The measured mechanical stability of the latex is longer than 400 seconds according to the reference standard.

Description

technical field [0001] The invention relates to a method for preparing synthetic latex, in particular to a method for preparing polyisoprene latex with high mechanical stability. Background technique [0002] Natural rubber latex has the advantages of easy film formation, high product elasticity and excellent skin affinity, and is widely used in the production of medical products such as medical gloves, condoms and urinary catheters. However, natural rubber latex contains a small amount of protein components, and its products can easily cause allergic reactions and endanger human health when it comes into contact with the human body. In addition, limited by climate and planting conditions, domestic natural rubber latex is inferior to that of Southeast Asian countries in terms of output and overall performance. Taking condoms as an example, more than 95% of domestic manufacturers use imported high-quality natural rubber latex as raw materials. The chemical composition of ar...

AI Technical Summary

Problems solved by technology

In order to resist the destabilizing effect caused by this high shear, the latex must have considerable mechanical stability, otherwise it is easy to gel and affect the use of latex

At present, there are few reports on the mechanical stability of synthetic polyisoprene latex at home and abroad.

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