The invention discloses an
isosorbide-based heat-resistant yellowing-resistant
biodegradable polyester and a preparation method thereof.The preparation method comprises the following steps that under the condition of an esterification catalyst,
dibasic acid and dihydric
alcohol are subjected to an
esterification reaction, the
dibasic acid is composed of
terephthalic acid and 1, 1-cyclohexanedicarboxylic acid, and the dihydric
alcohol is composed of 1, 1-cyclohexanedicarboxylic acid; the dihydric
alcohol is composed of
isosorbide and aliphatic dihydric alcohol; after the
esterification reaction is finished, adding a polycondensation catalyst, a stabilizer and a toner into an
esterification reaction product to carry out
polycondensation reaction; after the
polycondensation reaction is finished, the polycondensation product is subjected to bracing and grain-sized dicing, and the
isosorbide-based heat-resistant and yellowing-resistant
biodegradable polyester is obtained. 1, 1-cyclohexanedicarboxylic acid is introduced to replace part of
terephthalic acid, aromatic ring structures on
polyester chains are reduced, the yellowing resistance of
polyester is improved, meanwhile,
biomass-sourced isosorbide is added as a heat-resistant modified component, and the isosorbide-based heat-resistant and yellowing-resistant
biodegradable polyester is obtained through a direct esterification method.