Preparation And Performance Study Of Nano-TiO₂ Modified C9 Petroleum Resin

The C9 petroleum resin,as a functional thermoplastic resin with outstanding chemical and water resistance and low price,was widely used in paint and other fields in recent years.However,it will degrade if exposed to ultraviolet for too long.The nano-titanium dioxide（TiO₂）,as a inorganic material with outstanding heat resistance and ultraviolet shielding ability,was widely used to improve the anti-aging properties of organic material.However,the compatibility problems between the resin and nano-TiO₂ was still existing.In this paper,the C9 petroleum resin were modified by the modified nano-TiO₂.Firstly,by using different silane coupling agents,such as the γ-methacyrl trimethoxysliane（KH-570）and the vinyl trimeoxysilane（KH-171）,the modified nano-TiO₂ with the coupling agent method were prepared.The influences of the kind and amount of silane coupling agent（5²5 wt%）,the concentration of ethanol（0¹00 vol%）,the reaction time（1⁵ h）,the reaction temperature（30⁹0℃）,pH value（3¹1）were studied to determine the optimal technological conditions.The results showed that KH-570,the content of KH-570 20 wt%,the concentration of ethanol 90 vol%,the reaction time 3 h,the reaction temperature 90℃,pH 5 were the optimal conditions.The lipophilic degree of modified nano-TiO₂ could reached 67.74% and the average size of nano-TiO₂ in ethanol dispersion was about 240.2 nm.The gravity sedimentation and surface angle test showed that the dispersion and stability of nano-TiO₂ in ethanol dispersion was improved and the hydrophobicity was increased,which was 118.36゜.The FT-IR and TGA showed that there were chemical bonds between the nano-TiO₂ and KH-570.The X-ray diffraction and UV-Vis absorption showed that the crystal form of nano-TiO₂ was not changed and it did not decrease the UV absorption.Secondly,the modified C9 petroleum resin were prepared with the in-situ polymerization.The effect on the resin yield,softening point and color with different the catalyst dosage（0.3¹.5%）,polymerization time（1⁵ h）,polymerization temperature（-10⁵0℃）and the amount of nano-TiO₂（0² wt%）were explored.The results showed that the optimal technological conditions were: the catalyst dosage0.6%,polymerization time2³ h,polymerization temperature 0℃ and the amount of nano-TiO₂ 0.3⁰.7 wt%.The softening point of the composite material was 168℃.The Gardner color number was 3.The Tg was 106.9℃ and the thermal stability was better than the C9 petroleum resin.The SEM and EDS showed that the nano-TiO₂ dispersed well in the resin matrix.The TGA showed that the resion with the in-situ polymerization had better thermal stability than the solution blending method.Finally,the thermal aging,artificial ultraviolet accelerated aging and the resistance to medium of the C9 petroleum resin and the modified C9 petroleum resin were studied.The results showed that the modified C9 petroleum resin with 0.5⁰.7 wt% the nano-TiO₂ has the smallest color and mass change.But the modified C9 petroleum resin did not change nearly after 60 days of aging.The modified C9 petroleum resin had the excellent resistance to UV aging.