Preparation And Characterization Of Poss-Based Hybrid Polyesteramides

Cage silsesquioxanes(POSS)are compounds of a nano-sized organic-inorganic hybrid Si-O-Si structure.Due to the special structure of POSS which will improve the polymer in terms of thermal stability,dielectric properties,mechanical properties,hydrophobicity,etc.,POSS will generally improve the polymer properties through two forms,namely physical modification and Chemical modification.The physical modification is generally done by blending the POSS with a polymer in the form of a rigid particle,wherein the POSS exists as a filler and enhances the modified polymer;and the chemical modification is a method of chemically reacting the POSS.It is introduced into the polymer molecular chain to modify the polymer from its molecular structure.The latter directly optimizes the polymer structure at the molecular level,so it is the most effective and widely used method.Polyester amide is a kind of resin with excellent comprehensive properties.At present,there are many methods for synthesizing polyester amide.However,there are few reports on ring opening polymerization of bisoxazoline compounds containing double carboxyl groups to form polyester amides.This topic mainly synthesizes POSS with different side groups and different chain lengths with double-carboxyl functional groups and then it undergoes ring-opening reaction with bisoxazoline at high temperature to produce polyester amide chains with ester and amide groups in the main chain.POSS with different side groups and different chain lengths.The thermal stability,hydrophobicity,etc.of the new polyester amides synthesized have been significantly improved.Firstly,T7-type trihydric silanes with different side groups are reacted with trichlorosilane with double bonds through a nick-closed-loop method to form T8-type olefin POSS with different side groups and different chain lengths.The structure was characterized by FT-IR,NMR and GPC.The polyester amides were then synthesized by reacting the dicarboxylate POSS with different chain lengths synthesized with the bisoxazoline compounds(1,3-PBO,1,4-PBO,etc.);the dicarboxyl POSS with different chain lengths,different The effects of the dicarboxyl POSS of the pendant group and the different bisoxazoles on the properties of the resulting polyester amides were characterized using FT-IR,GPC,DSC,TGA,XRD,and hydrophobicity tests to characterize their structure,molecular weight and different properties.The results showed that the longer the chain length of the POSS-generated polyester amide thermal stability is better,the hydrophobicity is not much difference;the side group is the POSS of the benzene ring relative to the side group is isobutyl-generated polyester amide.The thermal stability is better,but the hydrophobicity is poorer.The bisoxazoline contains better thermal stability of the phenyl ring and the POSS-generated polyesteramide.The dicarboxy POSS was added to the succinic acid/bisoxazoline system in different proportions in the form of the third component,and the resulting polyester amide was subjected to FT-IR,DSC,TGA,XRD,and hydrophobicity tests.Analysis of the structure and performance revealed that with the increase of POSS,the thermal stability and hydrophobicity of polyester amides increased significantly.