Structure and mechanical properties of lignosulfonate/waterborne polyurethane blends

POLY 494

Wenbing Xia1, Guojuan Cui2, Jing Wen2, and Jin Huang, huangjin@iccas.ac.cn3. (1) Deapartment of Applied Chemistry, School of Sciences, Wuhan University of Technology, Wuhan, 430070, China, (2) College of Chemical Engineering, Wuhan University of Technology, Wuhan, 430070, China, (3) Key Laboratory of Cellulose and Lignocellulosics Chemistry, Guangzhou Institute of Chemistry, Chinese Academy of Sciences, Guangzhou, 510650, China
The lignosulfonate (LS) modified waterborne polyurethane (WPU) was synthesized, and the strength and elongation were simultaneously enhanced when the LS content was 1.5 wt%. Thereafter, with increasing LS content, the strength increased, but the elongation gradually decreased. It indicated that the low LS loading (1.5 wt%) might facilitate the formation of star-like network, in which the LS act as the center of physical crosslinking and partly chemical crosslinking. Such network structure played a key role to simultaneous reinforcing and toughening. At the same time, the increase of strength attributed to rigid supramolecular complexes self-aggregated by LS when the LS loading were relatively high. The structures of LS/WPU blends were characterized by FTIR, DSC and DMA. Introducing LS cannot obviously change the chemical environments of soft-segment in WPU, but restricted the motion of hard-segment as well as hydrogen bonding between LS and hard-segment.
 

Polymers from Renewable Resources
6:00 PM-8:00 PM, Tuesday, August 21, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Polymer Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007