Study On Preparation, Structure And Properties Of Thermoplastic Vulcanizate/nanoparticles Nanocomposite

Thermoplastic Vulcanizate (TPV) is a kind of blends by mixing thermoplastic plasticsand thermoset elastomer with dynamical vulcanization. With the development of technology,the good comprehensive performance TPV has been produced and is applied in various fields.However, there are some shortcoming existing in TPV, such as high cost, low strength andpoor oil resistance. Therefore, a lot of work must be done to produce TPV with high strength,excellent heat and oil resistance, low hardness and low cost.This paper reported the preparation, characterization, and properties of EPDM/PP TPVsand TPEE/ACM TPVs nanocomposites. Though nanoSiO2could improve the strength ofEPDM/PP TPVs, the hardness also increased markedly, and only10phr nanoSiO2could beadded in the TPV. In order to produce TPV with high strength, low hardness and low cost, thenanoCaCO3modified by coconut oil, stearic acid and modified polyether silicone was addedin the TPV. EPDM/PP TPV has good comprehensive performance, but its heat and oilresistance is poor. Therefore, TPEE/ACM TPVs with excellent heat and oil resistance wasproduced by the two-step method. Finally, we studied effects of modified nanoCaCO3andnanoSiO2on rheological behavior, morphology, thermal stability, heat-aging property, physicmechanical properties and dynamic mechanical properties of the TPVs.From the research, the results were as follows: We could produce the goodcomprehensive performance EPDM/PP TPVs using phenolic resin and stannous chloridedehydrate as vulcanizing agent. When blending ratio of TPEE/ACM was60/40, TPEE/ACMTPVs could achieve the best comprehensive performance, and its quality change rate andvolume change rate were only14.5%and12.3%in150℃oil for48h. Morphology studyshowed that the dimension of EPDM particles decreased with the increase of nanoSiO2andmodified nanoCaCO3. Dynamic mechanical analysis showed that nanoparticle influencedthe glass-transition temperature of the nanocomposite. RPA study revealed that theprocessability of TPVs become poor by adding nanoSiO2, but modified nanoCaCO3had littleinfluence on the processability of TPVs. Thermogravimetric study and heat-aging studyindicated that thermal stability and heat-aging property could be improved in presence of nanoSiO2and modified nanoCaCO3. With the increase of nanoSiO2and modified nanoCaCO3concentrations, significant improvement in tensile strength, and elongation at break of TPVshave been achieved. When10phr nanoSiO2was added, the tensile strength of EPDM/PPTPVs was23.7MPa improved by35.4%, but the hardness was increased markedly. Thoughthe adding amount of modified nanoCaCO3reached50phr, the elongation at break ofEPDM/PP TPVs was562%improved by60.5%and the hardness was still low. The oilresistance of TPEE/ACM TPVs was excellent. NBR/PP TPV with good oil resistance isapplied in the temperature from100℃to120℃, and it is dissolved in the150℃ASTM3#standard oil for48h. However, when TPEE/ACM TPVs with20phr nanoSiO2was soaked inthe150℃ASTM3#standard oil for48h, its quality change rate and volume change rate wereonly12.1%and11.2%. Therefore, the TPV with high strength, high elasticity, excellent heatand oil resistance and low hardness could be achieved by choosing right blending materialand adding proper nano particle.