| Because of having excellent properties and good product performance, therefore,its application field in the latex industry is very extensive.especially the presulfurization latex with good flow, less crust, defoaming easily and products have advantage of good transparency. So as to make the properties of latex products becoming better and save energy,using speeding accelerator with flat vulcanization curve generally, and latex products with thin thickness curing in high temperature will affect the appearance, so need curing under the low temperature in general, but some varieties of accelerator at low temperature without promoting effect. At present, making use of traditional secondary amino curing accelerators(ZDC,TMTD,etc.) in the latex industry generally could generated the N-nitrosamines with carcinogenicityeasily among the process of producing, which cause serious damage to people's health.TBSI with a primary amine structure belongs to environment-friendly curing accelerator which have advantages of long scorch time and highly strength of vulcanized rubber,but it is melting point is high and curing speed is slower,so far, it is applied in the products of latex have not been reported. ZDiBC as a speeding level secondary amine type green curing accelerator with low nitrosamine,blending with both would be formed synergies, not only solves the problem of N-nitrosamines in latex products process but also expects to shorten the curing time and saving cost, get a relatively flat curing curve, make products' performance better. This topic adopts sulfur curing system, making accelerator TBSI?ZDiBC used in natural rubber latex, studing the effects of the TBSI?ZDiBC on the curing characteristics?mechanical properties and content of N-nitrosamine of NRL film have been studied. At the same time,the effects of dosage of TBSI/ZDiBC?blending ratio and storage time on the mechanical stability?thermostability?viscosity of concentrated latex, curing characteristics of latex film, mechanical properties and the influence of curing temperature on the curing characteristics of latex film, mechanical properties have been investigated. In addition,studing the influence of dosage of environmental accelerator TBSI/ZDiBC on the colloid properties of latex with two centrifugal and curing temperature on the curing rate of curing latex and taking the influence of curing temperature on the mechanical stability? thermostability?viscosity?curing rate of vulcanized rubber latex with different centrifugal times and mechanical properties of vulcanized rubber into account. Also making TBSI/ZDiBC as the accelerator acts on the concentrated NRL, using general CV?SEV? EV three distinctive curing systems, investigating the influence of distinctive curing systems on the latex film curing characteristics, mechanical properties and the hot air aging properties of curied NRL film.The test outcomes showed that:Making accelerator TBSI?ZDiBC used in natural rubber latex for preparation of cured film,there is not N-nitrosamine have been detected.When making the accelerator TBSI/ZDiBC blended used in natural rubber late,which film's curing rate,degree of cured and mechanical properties are better than latex film with used accelerator TBSI?ZDiBC alone in natural rubberl atex.When fixed dosage of accelerator,the curing rate of latex film maximum speed up26.78%than TBSI, and maximum speed up17.66%than ZDiBC; the curing degree of latex film could increase1.49times than TBSI and could increase1.06times than ZDiBC.The period of vulcanization curve flat extended,operational safety has also been improved to some extent. When the ratio of TBSI/ZDiBC was1:2, vulcanized rubber had the best performance.Increasing the proportion of TBSI/ZDiBC,the mechanical stability of concentrate NRL was reduced, thermostability and viscosity were enhanced; Increasing the dosage of promoting agent, both of the concentrated NRL with different centrifugal times the mechanical stability, thermostability and viscosity were enhanced first and then decreased. The more the times of NRL centrifuge, the greater the mechanical stability of NRL, and the smaller the thermostability%viscosity of natural rubber latex. With the extension of storage time, the mechanical stability of concentrated NRL dropped slightly at first, then raised and finally fall, thermostability reduced after the first increase; the changes of viscosity is very small; As the curing temperature rises, the mechanical stability of curied latex with centrifugal first time was increased, thermostability and viscosity increases after the first down, the mechanical stability and thermostability of curied latex with centrifugal twice was increased, viscosity increases with small amplitude, When vulcanizing under the same temperature,the mechanical stability of curied NRL increase with the increase of the times of centrifuge, the thermostability and viscosity of vulcanized latex decrease with the increase of the times of latex centrifuge.With increasing the accelerator TBSI/ZDiBC amount, curing rate of concentrated NRL film first increased and then decreased,100%modulus,300%modulus?tensile strength of vulcanized rubber rise before they are reduced; When elevated curing temperture,the curing rate of concentrated NRL film became faster, but the mechanical performance of curied rubber was increased and then reduced, when the curing temperature is100?,curied rubber got best performance.The curing rate of latex with centrifugal twice with increasing temperature, the fewer the times of centrifuge latex, the faster the curing rate of NRL. crosslinking density in concentrated vulcanized latex film with different NRL centrifugal times were increasing with curing temperature increases, but its100%modulus after the first increases back into balance,300%modulus first increases the decreases,the tensile strength and tear strength both decreases. In addition, The fewer the times of centrifuge latex, the better mechanical properties of concentrated curied latex film.In three kinds of curing systems, the mechanical properties of vulcanized rubber from CV, SEV and EV is reduced, but the curing speed of latex film with CV was slowest.The hot air aging properties of effective curing system is best followed by semi-efficient curing system; Complex considering, SEV optimal. |
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