http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Maleated Natural Rubber Compatibilized Natural Rubber/Halloysite Nanotubes Composites
Nabil Hayeemasae,Kannika Sahakaro,Hanafi Ismail 한국고분자학회 2020 폴리머 Vol.44 No.5
The properties of rubber composites depend strongly on the compatibility of the rubber matrix and particulate filler. The polarity difference between the two phases has always been the main concern. Natural rubber (NR) and halloysite nanotubes (HNT) are one of the examples of the incompatible system. In this regard, a suitable compatibilizer is recommended to mediate the interactions. In this study, the maleated natural rubber (MNR) with various amounts of maleic anhydride (MA) was introduced as a compatibilizer to this composite. By increasing MA contents, scorch and curing times were increased whereas the maximum torque and the torque differences exhibited the highest values at the MA content of 2 phr. Payne effect was also implemented to monitor their rubber-filler interactions. The MNR with 2 phr of MA exhibited the lowest filler-filler interaction as shown by a lower decrement of storage modulus at high strain. This rubber composite also exhibited the optimum tensile and tear strengths. It is clearly highlighted that application of the MNR with a suitable MA amount enables to increase the rubber-filler interaction significantly and therefore improve a HNT dispersion. Hence, the use of MNR provided the great potential to compatibilize NR and HNT.
Abdulhakim Masa,Siriwat Soontaranon,Nabil Hayeemasae 한국고분자학회 2020 폴리머 Vol.44 No.4
Sulfur and accelerators play very important roles in curing natural rubber, influencing the properties of rubber vulcanizates. Such properties are also associated with the microstructure of vulcanized natural rubber. In this study, the relationships between tensile properties, strain-induced crystallization behavior, and structural inhomogeneity were investigated with special attention to the ratio of sulfur to accelerator (S/Acc). Increasing the S/Acc ratio increased crosslink density, simply from having more of the crosslinking agent. The highest tensile strength was obtained at unit ratio (=1), which was associated with SIC behavior based on wide angle x-ray diffraction measurements. Reductions in both the tensile strength and crystallinity were noticed when the crosslink density was relatively high. Structural inhomogeneity of network structures induced by crosslinking was investigated by means of small angle x-ray scattering, which showed the increased size and improved homogeneity of distribution with increased S/Acc ratio.
Nureeyah Jehsoh,Abdulhakim Masa,Indra Surya,Hanafi Ismail,Nabil Hayeemasae 한국고분자학회 2022 폴리머 Vol.46 No.1
Reducing Payne effect of natural rubber (NR) composite has been a major challenge in composite’s preparation. In this work, the composite based on NR and sepiolite was focused. Reduction of Payne effect was successfully performed by introducing modified palm stearin (mo-PS) as compatibilizer. Sepiolite was fixed at 20 phr whereby the mo-PS was ranged from 0-3 phr. The properties were studied through curing characteristics, tensile properties and dynamic properties. The presence of certain functionalities of mo-PS was corroborated by Fourier transform infrared (FTIR) analysis. From cure properties, scorch and curing times decreased as a function of mo-PS due to the role of mo-PS as a secondary curing additive in vulcanization process. It was also found that mo-PS improved modulus and tensile strength of composites. The improvement was due to improved NR-sepiolite interactions arising from hydrogen bonds formed in presence of mo-PS. This was clearly verified by observing the Payne effect.