Segmented Polyurethane Reinforced with Microcrystalline Cellulose

V.S.CONTOS; N.E.MARCOVICH; S.NUTT; M. I. ARANGUREN; M.L.AUAD

Long beach, California, USA

Congreso; SAMPE 2006; 2006

SAMPE

The effects of the hard-segment content on the thermal and mechanical properties of segmented polyurethanes (SPU) reinforced with micro sized cellulose fibers were investigated. The SPU selected for this work was a thermoplastic polyurethane (TPU) prepared from 4,4-diphenylmethane diisocyante (MDI), 1,4-butanediol (BD) and poly(ethylene glycol) (PEG). Four sets of TPU were synthesized containing a constant soft-segment molecular weight of 2000 and a variable MDI/BD-based hard-segment content ranging 23-45 wt%. For each set, TPUs were reinforced with 0.1, 0.5 and 1wt% of cellulose. The study on thermal and mechanical properties was performed using DSC, DMA and tensile testing. The results show that hard-segment crystalline melting temperature was in the range of 175-200 ºC and soft-segment melting temperature was in the range of 10-25 ºC. With increasing cellulose content, tensile and dynamic storage modulus as well as glass transition and melting temperatures increased in all the series. KEY WORDS: Nanocomposites, Polyurethane (PU), Fiber Reinforcement - Natural