Design,Synthesis And Properties Of Polyester Materials Based On Citric Acid And D-Camphor

Polyester materials refer to the polymers that contain ester groups in its main chains.It can be prepared by polycondensation of a variety of different aliphatic diols and dicarboxylic acid.Aromatic polyesters have a wide range of applications because of their excellent thermal stability and mechanical properties.However,these aromatic polyesters were based on terephthalic acid rely on non-renewable resources such as petroleum.At present,human is more and more dependent on petrochemical resources and their derivatives.However,according to the estimation of relevant international organizations,the world's oil resources can only be used for 50 years.In addition,the excessive use of oil will cause environmental pollution.To solve this problem,we should reduce the dependent of the oil and search renewable resources to prepare polymer materials.1.we describe the synthesis and characterization of a bio-based aromatic monomer from citric acid,methyl 3-(methoxycarbonyl)furan-2-acetate(MCFA),which was originaly used to synthesize a set of thermoplastic polyesters with different linear ?,?-diols by polycondensation.Surprisingly,the obtained polyesters underwent cross-linking reactions spontaneously and exhibited elastomeric properties without adding any cross-linker or external initiator.In order to find out the cross-linking mechanism,FT-IR and 1H NMR were used and some supporting experiments were carried out to determine the chemical changes during cross-linking process.In addition,thermogravimetric analysis(TGA),differential scanning calorimetry(DSC)and tensile testing were used to investigate the thermal and mechanical properties of the obtained thermosets C-PE-ms.In a word,these bio-based thermosets in this article have the following advantages:(a)bio-based and biodegradable;(b)self-cross-linking,which was clean,free;VOC-free and safe.(c)high performance thermal and mechanical properties.2.Poly(butylene succinate)(PBS)is currently a widely used biodegradable bio-based polyester.In order to further improve the mechanical properties and thermal properties of PBS,a series of copolyesters were synthesized by copolymerization of camphor alcohol,which was originated from naturally occuring camphor.The structure and properties of the polyester were characterized using TGA and DSC.The results showed that the glass transition temperature(Tg)of the copolyesters increased significantly after the introduction of camphor alcohol,and the higher molecular weight polyester materials were readily obtained after the introduction of camphor alcohol.