Preparation Of Cationic Dyeable Polypropylene And Its Properties Study

Polypropylene(PP)fiber were welcomed by the vast number of consumers due to light weight,quick-drying,low cost.but it was limited in the field of clothing and decoration applications because of its structural characteristics.It is noteworthy that,cationic dyeable polyester fiber were used as an indispensable species about the study of the dyeability of polyester fiber which due to wide chromatography,high color fastness,bright color.In view of this,copolymerization and blending were considered as a method to preparing styrene and sodium styrene sulfonate copolymer P(St-co-Na SS)which was used as a modification additive for cationic dyeable polypropylene fiber.In this theies,the modified additive was prepared by free-radical emulsion polymerization that with better processing flowability and better processing flowability,which was melt blended with PP,and the dyeing problem of PP was effectively solved.Through the above research,the following conclusions:The linear random copolymer P(St-co-Na SS)was prepared and the properties of the copolymer and the reaction conditions were studied.The structural units of sodium styrene sulfonate(Na SS)in copolymers were characterized by fourier transform infrared spectroscopy(FT-IR)and nuclear magnetic resonance(1H-NMR).The effects of introduction of sulfonic acid groups on glass transition temperature and initial decomposition temperature were studied by differential scanning calorimeter(DSC)and thermogravimetric analysis(TG).The effects of sulfonation degree on the shear viscosity of copolymer were studied by rotation rheometers.The effects of reaction conditions on sulfonation degree of copolymers were studied.The results show that sulfonation degrees reach 6.68%(the zero shear viscosity is 19 620 Pa?s)when reaction time is 2 h,reaction temperature is 70 oC,the used initiator mass fraction is 0.6%,the molar fraction of sodium styrene sulfonate is 0.01.the copolymer shows the characteristics of pseudoplastic fluid and good processing fluidity.The crystalline morphology,hot melt properties and rheological properties of PP/P(St-co-Na SS)blends were systematically investigated.The results showed that the P(St-co-Na SS)did not change the crystal structure of PP,but reduced the degree of crystallinity of PP,that caused the melting point of the blends decreased from 162.1 oC to 161.8 oC,the crystallization temperature increased from 110.8 oC to 111.3 oC,and the crystallinity decreased from 36.6% to 27.2%.Compared the PP/P(St-co-Na SS)and PP/PS,the PP/P(St-co-Na SS)blends with higher melting point,higher crystallizing temperature because of the motion of the molecular chains was decreased by the polar effect and steric hindrance effect,while higher crystallinity due to the small quanitity of Na SS could act as plasticizer.PP and blends shows the characteristics of pseudoplastic fluid in the shear rate range of 101~102 s-1.However the PP/P(St-co-Na SS)blends also shows the characteristics of pseudoplastic fluid at ?<10-1 s-1 due to the effect of rheological properties of P(St-co-Na SS).The viscosity of PP and blends were decreased with the increase of temperature,but the effect of temperature on the viscosity of the PP/P(St-co-Na SS)blends is less due to the sulfonated groups.The effect of the dyeable modification addition on the dyeing properties of PP was studied.The results showed that the PP/P(St-co-Na SS)blends were prepared by copolymerization-blending method could be dyed with cationic dye,the K/S value is 2.6032 and the dye uptake rate is 38.4%.Compared with pure PP and PP/PS,the PP/P(St-co-Na SS)blends showed higher K/S value and dye uptake with disperse dyes.