| Recently the weapon designers have been paying more attention to silicone rubber because of its well heat-stability,good aging and outstanding damping property, especially in adhesion of special explosives,as many other sorts of adhesives which have excellent properties are not compatible with these explosives due to their sensitivity to impact and instability. The silicone rubber has stable structure, and is compatible with special explosives,but the weak interactions between its molecules and its low cohesive energe cause to the low adhesive intensity,leading to the limitation of useness of silicone rubber in military affairs.This paper is concentrated on adhesive intensity improvement of two components of the room-temperature-vulcanization silicone rubber adhesives to special explosives.The interaction betwween adhesive and the special explosives is improved effectively by useing acrylic acid,polyurethane,MQ silicone resin to modify silicone rubber,managing the surface of special explosives,reinforcing with filler.This paper explores the influence of the dosage and structure of modifying component, preparation process of the modified silicone rubber on adhesive properties,and study the influence of species, dosage and surface manage method of white carbon black fillers on heat-resistance property.We also choose carborundum to strengthen, and confirm the process technologe of special explosives adhesion.By these methods,the adhesive interaction to special explosives is improved effectively.Results show that modifying silicone rubber with acrylic acid,polyurethane, MQsilicone resin can reinforce the adhesive intensity to special explosives,thesilicone rubber adhesive which is modified by acrylic acid or MQ silicone resin is compatible with special explosives,but the silicone rubber adhesive which is modified by polyurethane is not compatible with special explosives.When modifying silicone rubber with acrylic acid,the proportion of acrylic acid and the 107 silicone rubber has much influnce on the degree of viscosity of the polymer,and the method of adding materials has influnce on the particle size of the polymer too.The reaction products obtained by adding initiating agent drop by drop have an better even granularity.The dosage of polyurethane has obvious influence on thermolysis and tensile intensity of the modified materials;also,the preparation process has much influence on the tensile intensity,but little influence on heat properties.The silicone rubber modified by polyurethane of glyceryl alcohol or ricinus oil are obviously different,the front has better tensile intensity than the latter one,but its heat properties is bad.MQ silicone resin is a kind of polysiloxanes composed of siloxanes of three or four functional groups.MQ silicone resin was used to reinforce two component RTV silicone rubbers of condensation-curing type.The reinforcing effectiveness mainly depends on the structure of MQ silicone resin including M/Q ratio and the content of hydroxyl groups.The compatibility of MQ resin with the silicone rubber relys on the M/Qratio and improved with tne increment of it. It was important for the best reinforcement that there existed suitable microphase separation and chemical combination between MQ silicone resin and the silicone rubbers.Therefore,the reinforcement was most effective as the M/Q ratio of MQ resin is 0.8 and the MQ contained a suitable number of hydroxyl groups.Different types of white carbon black have different influence on the heat properties of the silicone rubber, especially the white carbon black has unfavourable influence on the heat properties ,because of the active hydroxyl groups on the surface of the white carbon black. The heat properties of the adhesive would be worse with the increase of the dosage of white carbon black.However the whitecarbon black which is treated by silazane in advance can improve the heat properties in a certain extent.Choosing certain partical sizes of calcium carbonate and silicon carbide can reinfoce the silicone rubber ad... |
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