Abstract:
This research has concerned the preparation and adhesive application of Liquid Natural Rubber (LNR). The LNR was prepared by reacting natural rubber latex with phenylhydrazine at various conditions including phenylhydrazine content, oxygen flow rate and reaction time. Adhesive strength of the LNR was determined by a 180 degree peel test. It was found that the peel strength rapidly increased when the molecular weight (M, ) of the adhesive increased above 9x10 g/mol. This was accompanied with changing of fractured surface feature from a smooth-toward rough rupture surface as the M, was incrcased. Incorporation of various additives into the LNR improved peel strength of the low M, LNR by approximately 36 %,except for AEROSIL200 silica whe~e the peel strength increased by 4 times. In the case of high molecular weight LNR, however, the peel strength rarely increased. Finally, the effect of storage conditions on peel strength of the adhesive was explored and it was found that the peel strength slightly increased during the initial period (1-2 weeks) before reaching a plateau. Failure mode was also changed from cohesive to adhesive type as the storage time increased, regardless of the storage temperature.