Abstract:
Bio-based polymer products derived from renewable agricultural and biomass feedstock have become increasingly important as sustainable and eco-efficient products which can replace the products based exclusively on petroleum feedstock. Within this framework, the concept of bio-based engineeing elastomer (BEE) is proposed and demonstrated here as a practical solution. Large-scaled bio-based monomers, such as sebacic acid, itaconic acid, succinate acid, 1,3-propanediol, 1,4-butanediol and vegetable oils were chosen to generate polyester typed BEE (PE-BEE), poly(di-alkyl itaconate-co-isoprene) typed BEE (PDII), and poly(epoxidized soybean oil-co-decamethylene diamine) typed BEE （PESD）, which are linear and noncrystalline elastomers with low glass transition temperature (Tg) and crosslinkable groups. The nanoparticles such as silica, carbon black and even graphene were then introduced into the BEE matrices to successfully realize the great strengthening and improve environmental stability. (1) The acquired PE-BEE demonstrated excellent mechanical properties and advanced comprehensive performance. Various fundamental researches for the applied potential of PE-BEE including PE-BEE toughening Polylactide (PLA), PE-BEE/PLA thermoplastic vulcanizates (TPV), shape memory materials, low temperature oil-resistance elastomers and low voltage driven dielectric elastomers were extensively conducted and many new results were found out. On this basis, a pilot production line (100 ton/year) of PE-BEE was designed and constructed. (2) PDIIs with various side chain lengths and properties were synthesized by Redox initiated emulsion polymerization. Carboxyl groups were further introduced into polymer chain to increase the interactions between PDII chains and silica. By adjusting the side chain lengths and the mole ratio of di-alkyl itaconate to isoprene, the dynamic viscoelasticity of PDII could be flexibly tailored for the requirement of green tires and other rubber products. PDII latex with and without pyridine group are co-coagulated with natural layered silicate/water suspension, and the resulted nanocomposites exhibited excellent air barrier property. PDII/hindered phenol hybrids were also successfully prepared, which displayed the excellent damping performance. Furthermore, 10L-scale PDII reaction kettle was designed and constructed, and 2 kg PDII could be prepared each batch. Preparation of PDII tires and the investigation of tire performance were in progress. (3) PESD was synthesized by ring-opening polymerization from epoxidized soybean oil and decamethylene diamine. The tensile strength of cross-linked PESD could be adjusted by using different amounts of succinic anhydride as crosslinker. The final elastomer possesses good damping property, low water absorption, and low degradation rate. (4) What’s more, as many tissues in the body have elastomeric properties, successful replacement or tissue engineering of pathological parts require the development of compliant biodegradable elastomeric scaffolds that readily recover from relatively large deformations. Our research group prepared several novel biodegradable elastomers based on biocompatible acid and alcohol. Besides, the nano-hydroxyapatite, nano-silica and carbon-nanotube were separately incorporated into these elastomers. The results showed that these polyester typed biodegradable elastomers displayed excellent elasticity and adjustable biodegradation capability and fine biocompatibility. Plasticized starch was also investigated and found to possess low modulus and high biocompatibility. Consequently, foamed plasticized starch/PVA was prepared, which illustrated extremely good cell-compatibility. (5) Finally, as a naturally grew and rubber contained plant, the study on the planting and abstracting of Russian Dandelion was initiated again in China in 2011. The research progress of this biobased elastomer with another special natural rubber (namely Eucommia ulmoides) in China was briefly introduced.
Keywords: biobased elastomers, engineering, medical, natural rubber
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Biography：
B.E. Beijing University of Chemical Technology 1990, 06
M.S. Beijing University of Chemical Technology 1992, 12
Ph.D. Beijing University of Chemical Technology 1995, 12
Working experiences:
Assistant Professor, Beijing University of Chemical Technology 1995-1996
Associate Professor, Beijing University of Chemical Technology 1996-1998
Professor, Beijing University of Chemical Technology 1998-now
Visiting Scientist, University of Akron, USA 1999-2000
Postdoctor, Case Western Reserve University, USA, 2000-2001
Prof Zhang has been very active in the research field of rubber science and technology for over 25 years since his bachelor thesis in 1989 and has been leading the Center of Advanced Elastomer Materials (
www.caem.buct.edu.cn), which holds a leading position in China in the field of rubber science and technology and possesses an internationally well recognized fame. He is also the head of Key Lab. of Beijing City on Preparation and Processing of Novel Polymer Materials, the head of Engineering Research Center of Ministry of Education on Energy and Resource Saved Elastomers, and associate head of State Key Lab of Organic-Inorganic Composites, China. He is the fellow of China Chemistry Industry and Engineering Society, the fellow of China Materials Research Society, the fellow of China Composite Materials Society, the fellow of China Nano Science and Technology Society, vice president of China Rubber Division, vice president of China Polymer Materials Engineering Division, and vice president of China Micro-Nano Composites Division, etc. Currently, he is serving as an editorial board member of the “Journal of Applied Polymer Science (USA)”, “Rubber Chemistry and Technology (USA)”, “Plastics, Rubber and Composites: Molecular Engineering (UK)”, “Elastomers and Composites (Korea)” and other 9 Chinese scientific journals.
His current research interests are (I) preparation and processing of advanced and novel rubber nanocomposites, (II) complex structure description and the relation between multi-scaled structures and performance of rubber composites by advanced simulation methodology and instruments, (III) design, synthesis and processing of new generation Biobased Engineering Elastomers. His research center and team members also work on the bioelastomers, functional rubber composites, rubber recycling and reutilization, and specially serviced rubber materials and production design. Around these fields, he has published over 300 international papers on above subjects and some of them are in highly reputed journals such as Advanced Functional Materials, Macromolecules, Macromolecular Rapid Communication, Langmuir, Polymer, and Progress in Polymer Science. His papers have been cited by peers in a positive manner for over 3000 times (SCI system) with an H-index of 30. He is a (co-)author of 8 books (chapters) and has given over 60 plenary/keynote/invited lectures in international conferences and over 60 plenary/invited lectures in Chinese ones. He had chaired many sessions in international conferences and 4 times co-chaired conferences or taken the vice-chairman of program committee of International Rubber Conferences. He and his team members have filed 160 Chinese patents and 3 international ones, and over 100 of them have been proved. He has received many high reputed scientific awards from relative Association, Society, Ministry and Committee of China including prestigious “9th China Youth Scientific Award” and “National Invention Award”. In 2012, he received Spark-Thomas Award from ACS Rubber Division, Asia Research Award from Society of Chemical Engineering of Japan and Morand Lambla Award from International Polymer Processing Society, which were due to his important contributions to rubber science and technology.
Prof. Dr. Liqun Zhang