Preparation And Properties Of Maleic Anhydride Copolymerized-Toughened Transparent Composites

Recently,as a new type of composite material,the young-mass transparent composite material has been gradually accepted by people as one of the better functional materials and has been widely used in various fields such as agriculture,architecture,and optical instruments.However,for applications such as automotive glass,high-speed train windows,aircraft side windows,and aircraft windshields,which have higher requirements for transparency,the mechanical properties of transparent composites,especially their mechanical strength and impact toughness,are poor.Its use efficiency.Therefore,it is of great significance to study a transparent composite with low linear expansion coefficient,good fracture toughness and impact resistance.Unsaturated polyester resin(UPR)has good thermal stability and mechanical rigidity.However,due to defects such as insufficient toughness and large shrinkage of unsaturated polyester resin,its wide application is limited.In this paper,unsaturated polyester resin as the matrix and alkali-free glass fiber cloth as the reinforcing phase,to prepare a highly flexible and transparent composite material,through a series of toughening and modification of unsaturated polyester resin,in certain To a certain extent,the problem of transparent composites has been improved.In this thesis,maleic anhydride(MAH)was added to the unsaturated resin,and the unsaturated polyester resin was toughened and modified with maleic anhydride and styrene as co-crosslinking monomers.Maleic anhydride was copolymerized with styrene.The maleic anhydride-styrene random copolymer is produced,the length of the segment between the cross-linking points in the resin is increased,the density of the cross-linking point is relatively reduced,the brittleness of the product after the resin is cured becomes smaller,and the flexibility of the resin is enhanced.purpose.The results showed that when the addition of maleic anhydride accounted for 12% of the mass of styrene in the resin,the impact strength and elongation at break of the cast after curing were significantly improved,and the tensile strength and bending strength decreased less.Toughening modification of unsaturated polyester resin by butyl methacrylate(BMA)and butyl acrylate(BA)respectively improves the impact resistance and fracture toughness of UPR,and explores that they are different from unsaturated polyester resins.The effect of the mixing ratio of the mass on the mixing phenomenon,the gelling time,and the mechanical properties of the casted body after curing.The results show that when the mixed system of butyl methacrylate/unsaturated polyester resin has a mass ratio of 6:100,the impact resistance and fracture of the cast body are obtained when the mixed system of butyl acrylate/unsaturated polyester resin is 10:100.The elongation is better.Glass fiber cloth is used as a reinforcing material to prepare a transparent resin matrix composite material.Due to the difference in the refractive index between the resin matrix and the glass fiber cloth,scattering and refraction occur when the light passes through the two-phase interface,resulting in the preparation of The transparency of composites does not meet actual needs.Therefore,methyl methacrylate(MMA)was selected to adjust the refractive index of the unsaturated polyester resin so that the difference between the refractive index of the unsaturated polyester resin and the refractive index of the glass fiber cloth was reduced,and the difference was further improved,thereby further improving the transparency of the composite material.The results show that when the content of MMA accounts for 14% of the mass of the resin,the difference between the refractive index of the resin and the refractive index of the glass fiber cloth is less than 0.01,and the light transmittance at this time reaches a maximum value of 94.9%.Without affecting the flexibility of the composites,we studied the light transmittance of different proportions of MMA added in 12wt% MAH/UPR.It can be seen that with the increase of MMA addition,the light transmittance increases and 10wt% MMA has the best transparency.The light rate is 93.9%.It was proved that the toughness and transparency of the mixed ratio were significantly improved at this time.Finally,a composite material with high flexibility and high optical transparency was prepared.