Surface Modified Calcined Kaolin And Its Applied Research, Epdm Rubber Printing Roller Rubber Compound

This paper is a partial work of the "Scientific Research Project of MaomingScience and Technology Fund, Maoming City, Guangdong Prov.",-"KaolinModification and its Application in Printing Roller" The main work is to study the surface-modification of calcinated kaolin and its application in EPDM printing roller compound.Kaolin is a kind of lamellar silicate which is consisted of Al-O octachedron and Si-O tetrahedroid, and on whose surface there are a lot of hydroxy groups. Kaolin calcinated in high temperature loses the active hydroxy groups, which are easy to react with rubber, through dehydration and dehydroxylation. Generally, it is thought that the reinforcement of the calcinated kaoin filled in the rubber is badder than the uncalcinated kaolin's,and that the calcinated kaolin is hard to be activitily modificated by modifiers. Under this background and basing on the actuality that most of the light colored printing rollers are mainly filled with the more expensive white carbon black(silica) as reinforcing filler, the surface-modification of calcinated kaolin made in Maoming Fascikao Co. Maoming City, Guangdong Prov., is majorly investigated in the paper with surfactants such as polyether N-210(Abr., PIPG 1000),diethylene glycol(DEG),polyethylene glycol 400(PEG 400), and with coupling agents such as A-172,A-187,Si-69,and with the blends of coupling agent and surfactant.In addition, the influences of above agents on the vulcanizing properties, the physical mechanical properties and anti-solvent properties of EPDM have been studied when the calcinated kaolin is used as the reinforcing filler of EPDM printing roller. The main results of this investigation are showed as follow : 1. N-210 and DEG can cause some surface-modification effect on the calcinated kaolin. When the dosage of N-210 is 0.5 phr , the tensile strength of the vulcanizates increases 25%, but the improvement of tear strength is not obvious; 2. Coupling agent A-172 and A-187 can cause obvious surface-modification effect on calcinated kaolin. When the content of A-172 is at 0.5 phr, the tear strength of the vulcanizates increases 59%, but the improvement of tensile strength is not obvious; 3. Through blending coupling agent A-172 with N-210, when the weight ratio is at 0.25/0.25, the tensile strength and tear strength of vulcanizates can be improved to a certain extent at the same time. As for the the...