Construction And Application Evaluation Of Anti-heat Accumulation Long-term Stability Vulcanization System

Vulcanization refers to the process of chemically cross-linking linear macromolecular chains in rubber through a vulcanization system under a certain pressure,temperature and time to form a three-dimensional network structure.It Is one of the most important parts in rubber processing.The early vulcanization phenomenon of the rubber during processing or parking before vulcanization,also known as self-sulfur,will make the processing of rubber difficult in subsequent operations,affect the physical properties of the product and the smoothness and planeness of the outer surface,or even cause the product joint to break Opening,etc.,greatly shortened the storage life of semi-finished rubber.At the same time,when using ordinary sulfur compound,rubber or products are prone to blooming,which affects the dispersion of sulfur,which will lead to uneven vulcanization reaction and seriously affect the performance of products.In response to the above problems,this paper first explored the construction of a hightrans polyisoprene(TPI)composite sulfur vulcanization system and the role of delayed scorch,kneaded TPI by using an open mill,and then mixed with sulfur in the internal mixer uniformly.TPI compound sulfur was obtained by freeze-drying with liquid nitrogen and then crushed.By comparing the vulcanization characteristic curve of common sulfur vulcanization system,the scorch time of TPI compound sulfur vulcanized rubber was significantly improved.In order to further explore the effect of TPI compound sulfur on the storage life of semi-finished rubber,the storage life prediction method model of semifinished rubber compound was established with reference to the rapid determination method of the storage period of static seal rubber parts.Based on the scorch time obtained under different temperatures and different aging times of 50% Sulphur Mixer.The storage life of the rubber at different temperatures was calculated.The calculation results showed that the storage life of this kind of rubber compound was about 57 days at room temperature of 20?.Since the softening point of TPI is about 70-80?,the temperature of sulfur addition in the preparation of the compound sulfur cannot exceed 80?.In this way,the vulcanization process needs to be kept at a low temperature during the processing,which will greatly change the vulcanization process and increase the processing cost.Secondly,this paper has been studied the preparation of polyethylene wax(PE wax)coated sulfur and its application in rubber vulcanization.Puted the three kinds of PE wax in a solvent to heat up to melt,and continue stirring and cool the temperature to promote the PE wax to use insoluble sulfur as the nucleus to form a shell structure of three kinds of coated sulfur.By using Fourier transform infrared spectrometer,FT-IR),polarizing optical microscope(POM),scanning electron microscope(SEM),and Malvern laser particle size analyzer(Zetasizer)to test and analyze the coated sulfur to confirm that the sulfur surface was successfully coated PE wax.The research results showed that the average particle size of the three types of coated sulfur was smaller than that of ordinary sulfur and had good dispersibility.Applying the three types of PE wax coated sulfur to the vulcanization process of natural rubber,it was found that not only the frost spray phenomenon was effectively avoided,but also the scorch time properly extended,so that the physical properties of vulcanized rubber has been improved,indicating the feasibility and effectiveness of this method.Finally,in this paper,PE wax-coated sulfur was initially used in the shoe strip rubber and outsole rubber.It was found that the vulcanization characteristics,physical and mechanical properties and anti-heat accumulation resistance of the products were significantly improved,which the effect was more obvious acted on the strip rubber,which further proved the feasibility of PE wax-coated sulfur used in actual production.In order to optimize the long-term s Tab.vulcanization system with PE wax-coated sulfur as the core and heat resistance accumulation,different types of PE wax and proportion were used to prepare the coated sulfur,and they were used in the vulcanization process of the adhesive tape.Long-term monitoring of the vulcanization characteristics of each sample and calculation of the storage life of the compounded rubber,and comprehensive comparison of the physical and mechanical properties of each sample,it founded that when using DA2 wax and sulfur coating ratio of 2: 3,the prepared PE wax-coated sulfur has the best performance and effectively solved the problem of frost spraying and scorch during the processing of products.