Study On Properties Of Cellulose Reinforced Polyurethane Composite

Po1yurethane(PU)has been widely applied for the excellent comprehensive properties.In order to widen the realm of its application,this paper on the one hand uses4,4-diamino-3,3dichlorodiphenylmethane(MOCA),Bisphenol A(BPA),polyether polyol of 1,3,5-tris(2-hydroxyethyl)isocyanurate(THEIC)derivate(320),trimethylolpropane(TMP)as crosslinking agent to prepare PU materials in 307 and 330N-MDI-DEG system.On the other hand,uses PU as matrix material,modified Methyl cellulose and ethyl cellulose(biodegraded organic filler)as filling to prepare high MC or EC/PU composite materials.The composites were characterized by a series of test methods.The results showed that polyurethane are prepared by using four types of crosslinking agent,MOCA is an optimum crosslinking agents for obtaining excellent mechanical properties,and PU prepared with TMP ascross-linking agent has excellent heat resistant performance,but an overall performance analysis shows PU prepared with MOCA as cross-linking agent is better than that of PU prepared with other crosslinking agents.The PU / MC composites are prepared by one step method in 307 and330N-MDI-DEGsystem system.Contact Angle test showed contact angle decreases with increasing MC content,which means that the introduction of MC enhance the hydrophilia of PUcomposites.The tensile strength and elongation-at-break of the composite containing only1.5 wt % MC were increased by 26% and 35% compared with that of neat PU,respectively.TGA shows that the heat resistance of polyurethane composite increase with increasing MC content.The PU/EC composites are prepared by one step method in 307 and 330N-MDI-DEG system system.Contact Angle test shows contact angle increases with increasing EC content,which indicates that the introduction of EC enhance the hydrophobicity of PU composites.The tensile strength only 1.5 wt % EC is increased by 32% compared with that of neat PU respectively,and the elongation at break shows a trend of decline.PU was covalently grafted onto the MC/EC by particular association with the hardsegments,as evidenced by FTIR and DMA.The adequate dispersion and network structure of MC/ EC in the PU matrix and the strong interfacial interaction through covalent grafting and hydrogen bonding between MC/EC and PU.