Design and synthesis of novel aminosiloxane crosslinked linseed oil-based waterborne polyurethane composites and its physicochemical properties

Abstract

A series of linseed oil based waterborne polyurethane-silica (LMGWPU-Si) hybrid materials with different weight ratios of 3-aminopropyl trimethoxysilane (APTMS) were synthesized successfully. Thereinto, linseed oil monoglyceride (LMG) was synthesized with glycerin (GL) and linseed oil (LO) by a transesterification process. Fourier transform infrared spectra (FTIR) result verified that the crosslinking interaction between polyurethane and APTMS. Scanning electron microscope (SEM) was used to represent the morphology and fracture surface of the LMGWPU-Si composite films, and the result showed that the LMGWPU-Si films were rough and possessed many small bumps. The thermal properties of WPU films and LMGWPU-Si composite films were tested by differential scanning calorimetric (DSC) and thermogravimetric analysis (TGA). TGA tests showed that the addition of APTMS increased the thermal stability of the composite films. DSC measurements proved that the addition of APTMS increased their glass transition temperature. Moreover, APTMS in polyurethane matrix significantly improved their mechanical properties. The contact angle and water resistance tests indicated that the synthesized LMGWPU-Si composite films possessed good hydrolysis resistance. These excellent performances endowed the LMGWPU-Si films with great potential in the surface material areas.