Preparation Of Biomass Dye/PBAT Masterbatch And Application In Fiber

With the growing awareness of environmental protection and the promotion of the concept of sustainable development,environmentally friendly biodegradable polymers are gradually replacing traditional polymers and are widely used.The research and application of biodegradable polyesters represented by polybutylene adipate-terephthalate,polylactic acid,polybutylene succinate,etc.have gradually deepened.Poly(butylene adipate-co-terephthalate)(PBAT)has gradually become an ideal biodegradable polyester to replace traditional polymers in recent years due to its good thermal properties,mechanical properties and processability.With the rapid development of chemical fiber industry today,the application of biodegradable polyester in fiber materials not only alleviates the problem of environmental pollution,but also implements the concept of green,environmental protection and low carbon,which has broad development prospects and application advantages.Biomass dyes are used in dyeing process,with a wide range of sources,variety and low cost.Its application can realize the greening of dye preparation,the cleaning of fiber dyeing and the ecologicalization of fiber products.Traditional synthetic dyes are widely used in various fields,but their application in biodegradable polymers has reintroduced non-biomaterials,so that the residual dyes after the waste and degradation of polymers will still pollute the environment.In this regard,people have gradually shifted the research focus to biomass dyes,in order to be able to cooperate with biodegradable fibers,so as to realize the green application of dyed fibers.In this paper,PBAT was used as the matrix material,and the biomass dye/PBAT masterbatch was prepared by blending with biomass dye,and then the PBAT dope dyed fiber was prepared by melt spinning method,and its basic physical properties and color were studied.The specific research process is as follows: first,the color structure,particle size and thermal stability of various common natural dyes are studied and screened,and the biomass dyes suitable for PBAT are preliminarily determined.Then the dye components were blended with PBAT powder,the effects of heat,force and other factors on the stability and blending compatibility of PBAT masterbatch were studied.A combination of silane-coupling dispersants and ultrasonic aids is proposed to solve the problem of dye agglomeration in polymer matrix and fiber forming.The effects of biomass dye addition on the rheological properties,thermal properties,dispersibility and color of PBAT were further studied.The results show that the degree of agglomeration of dyes in the PBAT matrix increases with the increase of the amount of dye added.The addition of trace dye components(1?5wt%)increases the Avrami index n of the system,which acts as a nucleating agent,and increased the crystallizing power of PBAT.In addition,according to the analysis of the rheological behavior of the PBAT masterbatch,the introduction of the dye components into the system hinders the melt flow during the melt blending process,generating additional forces and promoting the degradation process at high temperatures.In addition,there are active amino groups on the molecule of indigo dye,which will react with the molecular chain by ester-amide to cut off the macromolecular chain and accelerate the degradation,which further reduces the apparent viscosity and relative viscosity of the color masterbatch after thermal processing.However,due to the introduction of powder,it has a significant impact on the fluidity of the melt.In order to achieve melt spinning under high shear,it is still necessary to increase the spinning temperature and maintain good melt processing performance.Finally,the obtained PBAT base color masterbatch with a biomass dye content of 10wt% was blended and melt-spun with PBAT chips,and the dope dyed PBAT fiber was prepared by a two-step drawing method.The effects of the addition amount of color masterbatch and different draft ratios on the mechanical properties and color of PBAT fibers were studied.The results show that the optimum spinning temperature of PBAT dope dyed fiber is 270?.Fiber strength and crystallinity increased with the improve of draft ratio,while elongation at break decreased.The introduction of dye components promoted the crystallization process of fibers,and the crystallinity gradually increased with the increase of dye content.When the effective dye content was 0.3wt%,the color concentration of PBAT fibers reached saturation,L*a*b* value and reflectivity It tends to be stable,and the color fastness to washing can reach grade 5.