Study On The Adhesion Between Addition-type Silicone Rubber And Nylon

A new type of composite kitchenware products can be prepared from nylon for built-in support and addition-type silicone rubber for cladding layer. With low polarity, addition-type silicone rubber is a nonpolar polymer. Adhesive properties between addition-type silicone rubber and nylon were bad, which greatly limits compound and application by addition-type silicone rubber and nylon. In order to overcome the disadvantage of addition-type silicone rubber, a novel type of silicone adhesion promoter and a novel type of primer were prepared and applied to enhance the adhesive performance between addition-type silicone rubber and nylon. The main research contents and achievements are as followings:(1)By grafting UAIEM onto poly(methylhydrosiloxane)(PHMS) via hydrosilylation reaction, adhesion promoter wj was synthesized and applied to addition-type silicone rubber for enhancing the adhesive performance between addition-type silicone rubber and nylon.The reaction temperature, dropping speed of UAIEM, stirring speed, Pt catalyst concentration, value of n(Si-H)/n(C=C) were 80℃, 10 ~ 15 d/min, 500 ~ 900 r/min, 1.2 ppm and 1.00, respectively. On the condition, the yield of adhesion promoter wj was 77.5%. The adhesion promoter wj had the optimum adhesion promoting property, whose shear strength of between nylon and addition-type silicone rubber containing adhesion promoter wj was3.48 MPa.(2)The effect of the amount of adhesion promoter wj on vulcanization, crosslinking density, mechanical properties, adhesive property, medium-resistance performance and extractive content of addition-type silicone rubber were studied. While the adhesion promoter wj content was 7 phr, optimum performances of the addition-type silicone rubber were attained.The crosslinking density of the vulcanized rubber was 58.32×10-5 mol·cm-3, as well as stiffeness 54 degree, tensile strength 9.8 MPa, elongation at break 481%, tear strength 23.0 k N/m,extractive content 0.3%. The adhesion promoter wj had the optimum adhesion promoting property whose shear strength of between nylon and addition-type silicone rubber containing adhesion promoter wj was 3.48 MPa. At the meantime, medium-resistance performance between nylon and addition-type silicone rubber was excellent. When the addition-type siliconerubber soak at normal heptane 25 h and ethyl alcohol 20 h, respectively, the value of extraction decreased obviously. Hygiene index of addition-type silicone rubber reached the Health Standard of EU.(3)With γ-(2,3-epoxypropoxy)propytrimethoxysilane(KH560) and 2-Isocyanatoethylmethacrylate(IEM) as main raw materials, primer was prepared and applied for enhancing the adhesive performances between addition-type silicone rubber and nylon. The primer had the reversely best combination property when the molar ratio between KH560 and IEM was8?2. The shear strength of between nylon and addition-type silicone rubber was 3.48 MPa.Etching the surface of nylon by different solvents, the adhesive performances between addition-type silicone rubber and nylon could be improved. When sulfuric acid was utilized to etch the surface of nylon, the adhesive performances between addition-type silicone rubber and nylon was further improved. The shear strength of between nylon and additiontype silicone rubber was 6.68 MPa. At the meantime, medium-resistance performance between nylon and addition-type silicone rubber was excellent. Due to epoxy group and-NCO group of addition-type silicone rubber surface, the interfacial adhesion between nylon and addition-type silicone rubber could be enhanced effectively. With the physical table force and intermolecular force, the interface adhesive force between nylon and addition-type silicone rubber increased. Compare with adhesion promoter, the adhesive performance between addition-type silicone rubber and nylon were better by primer.