The Synthsis Of SSBR Functionalized In Chain Via Click Chemistry And Its Performance Enhanced By Carbon Black

With the development of society,people demand for energy is more and more urgent,Products with energy-saving is particularly important for the lack of energy.The application of solution styrene butadiene rubber(SSBR)is becoming more and more extensive in modern society,such as in the use of car,etc.So the modification of solution styrene butadiene rubber to be an energy saving,low cost and high performance materials is extremely urgent.The article is about on the rubber side chain,which is grafted by functional groups such as siloxane groups,hydroxyl groups or carboxyl groups according to thiol-ene click reaction,so as to enhance the compatibility of rubber and carbon black,in order to realize the purpose of high performance of styrene-butadiene rubber.Firstly,the properties of modified rubber was carried out by testing methods of 'H-NMR,GPC.The modifying agent is 3-mercaptopropyltriethyoxasilane and 3-mercapto-1-propanol.The calculation method of click rate was established.We mainly studied effects of click percentage about reaction time/reaction temperature/atmosphere/the amounts of initiator/the amounts of mercaptan/reactant concentration and so on.It was found that it had equivalent effects on improving reaction temperature and extending reaction time.We can get different click percentage by reasonable choosing different reaction time and reaction temperature;The reaction was better in inert atmosphere,The better ratio of initiator and the amount of mercaptan was nLPO:nRSH = 1:120?1:150.The click percentage of SSBR-g-S(CH2)3-Si(OC2H5)3 reached by 17.86%,and the SSBR-g-S(CH2)2COOH reached by 18.52%.The Tg of SSBR-g-S(CH2)3-Si(OC2H5)3 polymer was not obvious,but the molecular weight of SSBR-g-S(CH2)3-Si(OC2H5)3 grafting polymer was increased with the increase of grafting percentage;The Tg of SSBR-g-S(CH2)2COOH polymer was obvious went up,and its molecular weight also increased.Secondly,the performance of modified rubber was characterized by methods such as DSC,RPA,DMTA,the rubber was reinforced by carbon black/silica.The results showed that SSBR modified by siloxane didn't apply to carbon black enhance system,while was good in silica system;The performance of SSBR functionalized in chain by hyroxyl was improved,the rubber was reinforced by carbon black.When grafting percentage was 3.52%,the tensile strength of SSBR-g-S(CH2)3OH rubber reached by 22.5 MPa,tear strength increased 2.2 kN/m,at the same time,the elongation at break decreased sharply with the increase of grafting percentage.Payne effect obviously decreased,compared with carbon black inhanced pure rubber,so the scattering of carbon black was good.The performance of 6-mercapto-1-hexanol modified SSBR rubber(SSBR-g-S(CH2)6OH)was excelent when grafting percentage was 3.35%,the tensile strength reached by 21.8MPa,Payne effect decreased.The mechanical properties of 3-mercapto propionic acid modified SSBR rubber(SSBR-g-S(CH2)2COOH)obviously increased when grafting percentage was 1.74%,which tensile strength reached by 26.6MPa and tear strength increased 11 kN/m,Payne effect obviously decreased,which was compared with pure rubber reinforced carbon black.As for modified rubber,tan? at 0 ? increased,tan? at 60 ? decreased.SSBR-g-S(CH2)3OH enhanced by ZnCl2 and carbon black,according to adding ZnCl2,we introduced the coordinate bond,which tensile strength reached by 25.5MPa,when the grafting percentage was 4.52%.The tensile strength of SSBR-g-S(CH2)2COOH enhanced by ZnCl2 and carbon black reached by 26.7MPa when grafting percentage was 7.25%,which introduced the ionic bond.the experiment results showed that SSBR-g-S(CH2)2COOH rubber had "self crosslinking"effect.Compared with performance of three kinds of rubber functionalized in chain,SSBR rubber modified by nonpolar siloxane groups improved very small,the stronger polarity of hydroxyl groups improved well,the strongest polarity of carboxyl groups improved best;According to the contrast of performance of two hydroxyl groups modified SSBR rubber,the polar groups distance closer to main chain of rubber was better,which inhanced by carbon black system.