Research On Preparation And Thermal Stability Of Polyoxymethylene Color Masterbatch

The C-O bond in polyoxymethylene(POM),as an essential structural unit,always serves as linker between two repeat units.However,due to its less thermostability,the C-O bond is easy to thermal decompose into formaldehyde,which limited the application of POM materials.Thus,the main purpose of this thesis is to obtain a widely used formula for polyoxymethylene dyeing of various pigments,through investigating the impact of various additive chemicals on the thermostability of POM.In this thesis,the HAAKE rheometer is used to investigate the influence of different pigments(red,yellow,blue)on the thermal stability of polyoxymethylene.The experimental results show that Yellow3 RLP displays a most negative impact on the thermal stability of POM.In particular,with an addition amount of 5%,POM has already seriously foamed.Therefore,Yellow3 RLP is selected as the main research object to enhance the thermal stability of the corresponding POM-pigment system and subsequently obtain extended formulas to other pigments.Subsequently,the thermostability and additives synergistic effect of POM-Yellow3 RLP system were investigated by adding nitrogen-containing compounds,antioxidant compounds and double-bonding compound auxiliaries to the reaction system.The experimental results show that one-component additive reveals mild improvement while the three-component formula based on CaSt+ABS effectively promote the thermal stability of the system.Moreover,the multi-component formula of ABS+EBS+ COPA+Cast+hydrazide are turn out to be the optimized CaSt+ABS based formula to effectively promote the thermal stability of POM products with a 10% content of the yellow pigment.Subsequently,by extending the optimized formula to various pigments,15% and 25% contents of the unstable blue pigment and the stable red pigment were measured respectively.In conclusion,through investigating the thermostability of the POM masterbatch,we observed the impact of various reaction parameters on each POM-pigment system,which is of great significance for the synthesis of POM masterbatch.Additionally,the optimized formula obtained in this thesis presents widely applications that various POMs can keep good thermostability without any undesirable phenomena under less than 2% pigment content.