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Carbon nanotube-reinforced elastomeric nanocomposites: a review

This review is focused on carbon nanotube (CNT)-elastomeric polymer nanocomposites, which have attracted industrial and academic interest over the years due to their enhanced properties. Major factors notably CNT type, surface modification, dispersion of CNT, and processing techniques that affect the physical properties of CNT-elastomeric polymer nanocomposites are reviewed, and several key physical properties, including tensile, electrical, and thermal properties, were also included in this review. Some of the key challenges that undermine the effectiveness of CNTs and their composites with elastomeric polymers, and the potential applications of CNT-elastomeric composites are also captured.

Autohesion Behavior of Brominated-Isobutylene-Isoprene Gum Nanocomposites with Layered Clay

대학원 디자인제조공학과접수일(2014년 2월 10일), 수정일(2014년 2월 24일), 게재확정일(2014년 2월 28일)ABSTRACTThe effect of nanoclay (Cloisite 20A) on the self-adhesion behavior of uncured brominated-isobutylene-isoprene rubber (BIIR) has been studied. The dispersion state of nanoclay into the rubber matrix was examined by SEM, TEM and XRD analysis. The thermal degradation behavior of the filled and unfilled samples was examined by TGA and improvement in the thermal stability of the nanocomposites occurred based on the weight loss (%) measurements. Also, addition of nanoclay enhanced the cohesive strength of the material by reinforcement action thereby reducing the degree of molecular diffusion across the interface of butyl rubber. However, the average depth of penetration of the inter-diffused chains was still adequate to form entanglement on either side of the interface, and thus offered greater resistance to peeling, resulting in high tack strength measurements. The improvement in tack strength was only achieved at critical nanoclay loading above 8 phr. Contact angle measurement was also made to examine the surface characteristics. There was no significant interfacial property change by employing the nanoclay.요 약：브롬화 이소부틸 이소프렌 (BIIR) 고무의 점착성에 미치는 나노점토(Cloisite 20A)의 영향을 조사하였다. 고무내 나노점토의 분산성은 SEM, TEM, XRD으로 분석하였다. 나노점토 충전 및 미충전 고무의 열적안정성은 TGA로 분석하였으며, 충전고무에서 열적안정성을 보였다. 또한 나노점토를 첨가하면 보강효과에 의해 고무의 강도가 증가하였다. 나노점토 첨가로 계면간 분자확산 정도는 감소할 것으로 판단되었지만, 본 연구에서 관찰된 분자확산에 의해 형성된 계면의 두께는 분자사슬간 엄킴현상을 유발하는데 충분하여 계면점착력이 증가하는 것으로 나타났다. 계면점착력 증가현상은 일정한 이상 (8 phr)의 나노점토가 첨가되었을 때 나타났다. 나노점토 첨가에 따른 표면특성의 변화를 조사하기 위해 접촉각 측정을 하였는데 큰 변화는 관찰되지 않았다.Keywordsnanocomposites, autohesion, inter-diffusion, brominated-isobutyl-isoprene rubber