Synthesis of Bio-based Polyesters and Polycarbonates from Lipid Derived Monomers

• Author / Creator

  Jin, Liejiang

• Petroleum-derived polymers have applications in various industrial sectors including packaging, aerospace, automotive, adhesives, cosmetics, construction, medical and other industrial fields. Recently, due to dwindling fossil fuel resources and environmental concerns, both academia and industry has focused their attention on the development of biopolymers from renewable resources which could be eco-friendly and potentially biodegradable. Lipids are regarded as potential renewable resources for the synthesis of such biopolymeric materials. This thesis firstly reports a rapid and efficient route to convert lipids into a desired diester monomer and synthesis of polyesters from the monomer under microwave irradiation conditions. The plant oils were transferred into diester using microwave-assisted metathesis chemistry in solvent free conditions within few minutes at low temperature (50oC). The diester monomer was further modified to produce polyesters using conventional heating, microwave irradiation and conventional heating coupled with microwaves. The biopolyesters with number average molecular weight (Mn) as high as 30 kDa were synthesized. The biopolymer with desired molecular weight could be synthesized in less than half time using microwaves and coupled method compared to conventional heating method. Secondly, microwave-induced syntheses of lipids derived α-olefin to polyesters and polycarboantes were carried out. An α-olefin was converted to epoxide with >90% yield. Using ring opening polymerizations, this monomer was copolymerized with carbon dioxide (CO2) and different cyclic anhydrides including maleic, succinic, itaconic, phthalic and tetrahydrophthalic anhydrides to develop biopolymers under microwave conditions. The biopolymers were rapidly synthesized (3-30mins for CO2 and 10-60mins for anhydrides) with high conversions (up to 99%) and molecular masses (Mw) as high as 17 kDa. The synthesized monomers were characterized using different techniques including nuclear magnetic resonance (1H NMR & 13C NMR), fourier transform infrared spectroscopy (FT-IR) and gas chromatography- mass spectroscopy (GC-MS). The biopolymers were characterized using 1H NMR, 13C NMR, FT-IR, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), dynamic mechanical analysis (DMA) and tensile tests. The semi-solid to solid biopolymers with highest degradation temperature ~400°C, tensile strength ~ 5 MPa, and melting temperature ~ 50°C were synthesized with great potential to be used in different applications.

• Subjects / Keywords

  • Olefin metathesis
  • Microwaves
  • Lipids
  • Polymerization

• Graduation date

  Fall 2017

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3TM72F38

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.