| Styrene-butadiene-styrene block copolymer (SBS) is a thermoplastic elastomer, which has many excellent properties such as high stretch strength, low temperature durability, easily process, low surface friction coefficient, etc, and is widely used in rubber products, adhesives, modification of asphalt and waterproof materials,etc. Compared with other adhesives, SBS elastomer has both characteristics of plastics and rubber, which has good compatibility and adhesion to a variety of polymers. However, the molecule polarity and cohesive strength of SBS is low, which leads to poor adhesion and compatibility with polar materials. Modification upon SBS adhesives has been reported in many domestic and international researches, but literatures about moisture curing SBS adhesives are seldom reported. To overcome its disadvantages, to improve its physical performance and to extend serving temperature of SBS adhesive, polar groups– maleic anhydride and epoxy groups are introduced to the molecule chain of SBS by chemical reaction. In order to crosslink with water, siloxane groups are also introduced to SBS, which can increase its cohesion strength and extend its applications. The chief research contents and conclusions are as following:(1) Maleic anhydride grafted styrene-butadiene-styrene (SBS-g-MAH) block copolymer was modified withγ-aminopropyl triethoxysilane(KH550) in order to be moisture-curable. The effect of initial concentration of SBS and the content of MAH,KH550,terpene-resin on the structure and properties of products was characterized by FTIR,TG and T-style peel strength. The results indicate that when the initial concentration of SBS is 0.15g/mL, m(SBS):m(MAH):m(BPO):m(KH550)=10:1:0.06:1.2, and the mass content of terpene-resin is 90% by SBS, the corsslinking degree is 36.13% and the T-style peel strength to Polyethylene (PE),Polyethylene terephthalate (PET),Polyvinylchloride (PVC) has been improved.(2) SBS were epoxidized by peracetic acid generated from formic acid and hydrogen peroxide. The effect of initial concentration of SBS,the content of components,reaction temperature and reaction time was studied on the mass fraction of epoxy groups. When reaction time was 2h, reaction temperature was 70℃, initial concentration of SBS was 13%, and mole ratio was n(HCOOH):n(H2O2):n(C=C)=0.5:0.5:1, mass fraction of epoxy groups of ESBS was 13.2%. Then the effect of initial concentration of ESBS,the content of ESBS and KH550,reaction temperature and reaction time was studied on the grafting ratio of KH550. When reaction time was 4h, reaction temperature was 90℃, initial concentration of SBS was 25%, and mole ratio was n(KH550):n(Epoxy)=0.4, grafting ratio of KH550 attained 12.2%. Then the properties of products were characterized by FTIR,TG and T-style peel strength. When terpene-resin on the structure and properties of products were characterized by FTIR,TG,tensile shear strength and T-style peel strength. In the standard laboratory temperature (23±2℃) and humidity (65%) conditions, when n (KH550) / n (Epoxy) = 0.4, concentration of SBS was 25%, curing time was 48h, the crosslinking ratio was 65%. Then the properties of products were characterized by FTIR,TG and T-style peel strength. When terpene-resin on the structure and properties of products were characterized by FTIR,TG,tensile shear strength and T-style peel strength. The result shows that epoxy groups and moisture-curable groups have been grafted onto SBS, the thermal decomposition temperature and polarity of crosslinked ESBS was higher than that of SBS. And according to compatibility, the rosin ester was used as tackifier resin and added by different mass fraction of modified ESBS. When the material is PE, the T-style peel strength of ESBS was lower than SBS, but T-style peel strength of crosslinked ESBS was higher than SBS. T-style peel strength of modified ESBS reached 15N/25mm from 12.14N/25mm; The T-style peel strength of modified ESBS on PET and PVC reached 17.03N/25mm and 23.01N/25mm respectively from 12.65N/25mm and 15.38N/25mm. Finally the modified moisture curing SBS adhesive still possesses the peel strength at 90℃.
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