저분자량 폴리아크릴레이트를 첨가한 아이오노머의 기계적 성질 및 형태학

Abstract

In the present work, I had studied two ionomer systems; (1) blends of PMMANa and PEANa ionomers and (2) ionomers containing low MW PAANa. In the first part of the study, the relatively low Tg ionomer, PEANa ionomer, was mixed with relatively high Tg ionomer, PMMANa ionomer, and the mechanical properties of the ionomer blends were investigated. It was found that the PEANa ionomer acted as elastomer or plasticizer in the hard matrix of PMMANa ionomer, when the PMMANa was a dominant phase. On the other hand, the PMMANa behaved like glassy entities or filler particles in the rubbery matrix of PEANa ionomer, when the PEANa ionomer was a dominant phase. To interpret the mechanical properties of the ionomer blends, a number of models were applied to the data, which included Guth equation, rule of mixture, logarithmic rule of mixture, Halpin-Tsai equations for the regular system and inverted system. In the second part of the study, the roles of low MW PAANa oligomers in the PMMANa, PSMNa, and PSSNa ionomers were investigated. It was found that the phase-separated PAANa acted as filler in PSSNa ionomer. At low ion content, the PAANa increased the fraction of ion pairs that formed multiplets, and, thus, increased the modulus strongly. On the other hand, at high ion content, the PAANa acted as simply filler, and, thus, increased the ionic modulus, to some extent. In the case of PSMNa ionomer, phase-separated PAANa behaved like filler particles that acted as sites with which the ion pairs of the ionomer formed ionic aggregates. If this were the case, the ionomer would form a smaller number of multiplets than the ionomer without PAANa. Thus, the ionic modulus of the PSMNa ionomer was affected by both the less clustering and filler effect by the phase-separated PAANa. In the case of PMMANa ionomer that was known to be very weak clustered materials, the PAANa in the PMMANa ionomer acted just as filler particle. Thus, the presence of the PAANa in the ionomer did not affect the mechanical properties of the ionomer significantly.