Progress in polydimethylsiloxane-modified waterborne polyurethanes.

Preparing PDMS-modified WPU has attracted the attention of many researchers for two decades and this modification strategy has been proved to be an effective and feasible way to improve some key properties of WPU. In this review, both physical and chemical modification are introduced in depth. For chemical modification, the types of PDMS used, the copolymerization methods, the sub-classification of PDMS-modified WPU, and the synthesis processes are categorized and reviewed respectively; the effects of PDMS on colloidal, film-forming, surface, mechanical, and thermal properties as well as the effects of PDMS on microphase separation and hydrogen bonding behaviors of WPU are discussed in detail, with focus on the introduction to and understanding of the "structure-morphology-property" relationship of these hybrid materials. Besides, a current strategy to combine the PDMS modification technique with other modification methods to obtain novel WPU materials with superior properties is introduced. Finally, the challenges and future perspectives of this field are discussed.