Design And Preparation Of Re-processable Bio-Based Itaconate Elastomers

Rubber is widely used in our daily life due to its unique high elasticity.However,the rubber industry is currently facing two serious problems:(1)most rubber products are derived from petrochemical resources,which are increasingly in short supply;(2)rubber products that formed irreversible chemical bonds in the vulcanization process are difficult to recycle,resulting in a serious waste of resources.Therefore,it is important to research a re-processable non-petroleum-based rubber.Our term has been committed to developing bio-based elastomer materials that can be applied in engineering fields such as tires and footwear materials.Representative researches are itaconate elastomer and degradable polyester elastomer.In this thesis,furan-functionalized elastomers of two systems which were itaconate-myrcene copolymer and itaconate-butadiene copolymer were synthesized respectively based on previous researches of bio-based itaconate elastomer.By introducing Diels-Alder(DA)thermo-reversible covalent bonds,the topological rearrangement of DA crosslinking network at high temperature gave the material re-processability.In the first part of this thesis,furfuryl methacrylate(FMA)was selected as the modified monomer.Furan-functionalized all-bio-based itaconate elastomer which was named as poly(dibutyl itaconate-myrcene-furfuryl methacrylate)(PDBIMFA)was prepared via high-temperature emulsion polymerization.The particle sizes of latexes were characterized by a laser particle sizer,and its structure and composition were characterized by FTIR and ~1H NMR.The effect of different FMA contents on the structure and properties of PDBIMFA was also systematically investigated.This part of research provides a new idea for the preparation of furan-functionalized elastomer materials.In the second part of this thesis,based on Diels-Alder reaction,bismaleimide(BMI)and carbon black(CB)were introduced into PDBIMFA as crosslinking agents and reinforcing fillers respectively by melt blending method,and PDBIMFA-BMI elastomer material and CB/PDBIMFA-BMI elastomer composite with thermo-reversible crosslinking characteristics were prepared.The effects of the ratio of FMA and BMI on the mechanical properties of PDBIMFA-BMI were studied.PDBIMFA-BMI and CB/PDBIMFA-BMI were re-processed twice and these samples showed over 90%tensile strength recovery and good re-processability.The addition of carbon black was found to play a reinforcing role in the material.However,with the increase of amount of carbon black,the re-processability of composite became worse.In the third part of this thesis,based on the realized pilot scale poly(dibutyl itaconate-butadiene)rubber,FMA was introduced as the third monomer and furan-functionalized bio-based itaconate elastomer which was named as poly(dibutyl itaconate-butadiene-furfuryl methacrylate)(PDBIBFA)was prepared via low-temperature emulsion polymerization.The purpose was to achieve the re-processability of existing pilot products.PDBIBFA-BMI elastomer materials with thermo-reversible crosslinking properties were prepared by melt blending method.Compared with PDBIMFA-BMI,the tensile strength and elongation at break of PDBIBFA-BMI were both improved.Most importantly,these samples also maintained good mechanical property recovery rates.