Coupling agents nanocomposites

J. Kim, K. Lee, K. Lee, J. Bae, J. Yang, and S. Hong, Studies on the thermal stabilization enhancement of ABS synergistic effect of triphenyl phosphate nanocomposite, epoxy resin, and silane coupling agent mixtures, Polym. Degrad. Stab., 79(2) 201-207, 2003. 

S.-K. Yeh, A. Al-Mulla, and R.K. Gupta. Influence of the coupling agent of polypro-pylene/clay nanocomposite-based wood-plastic composites. ANTEC, Society of Plastic Engineers, Brookfield, CT, 2005, pp. 1290-1294. 

Fig. 3 Main features of the formation of sdica/polymer nanocomposite ptuticles through emulsion polymerization using MPTMS as silane coupling agent. Reproduced from [33] with permission of American Scientific Publishers...

Kim, S.J. Moon, J.B. Kim, G.H. Ha, C.S. (2008). Mechanical Properties of Polypropylene/Natural Fiber Composites Comparison of Wood Fiber and Cotton Fiber. Polymer Testing, Vol.27, No. 7, (October 2008), pp. 801-806, ISSN 0142-9418 Kotek, J. Kelnar, L Studenovsky, M. Baldrian J. (2005). Chlorosulfonated polypropylene preparation and its application as a coupling agent in polypropylene-clay nanocomposites. Polymer, Vol. 46, No. 16, (June 2005), pp. 4876-4881, ISSN 0032-3861... 

Nanocomposites with zinc oxide nanoparticles based on BPI have been fabricated from zinc oxide nanoparticles that are modified with 3-aminopropyltriethoxylsilane as coupling agent [22]. The zinc oxide nanoparticles effect an enhancement of the thermal stability of nanocomposite in comparison to the neat BPI. 

Abdolmaleki A, Bazyar Z. Preparation and characterization of poly(benzimidazole-amide)/ zno nanocomposites using silane coupling agent. Polym-Plastics Technol Eng 2013 52(15) 1542-9. 

Coupling agents have also been used in ternary nanocomposites, for example, in a paper by Hui et al. [67] who used a silane-coupling agent on LDPE/EVA elastomer (40/60)/3 wt% silica composites. They observed dramatic improvements in the mechanical properties (increase of 41% for the tensile strength) that were attributed to the reduced agglomeration tendency of the particles, as proved by AFM. 

Kotek, J., Kebiar, I., Studenovsky, M., and Baldrian, J. 2005. Chlorosulfonated pol5q)ropylene Preparation and its applications as a coupling agent in polypropylene-clay nanocomposites. Polymer 46 4876-4881. 

IR based nanocomposites. In situ silica was prepared in IR with the solution process.Swelling experiments evidenced good polymer-filler adhesion, in the presence of coupling agents. The dynamic-mechanical behaviour was found to be increasingly non-linear for silica contents higher than 20 wt%. 

For NR nanocomposite filled with silica, it has always been known that the hydrophilicity-hydrophobicity issue is a challenge since silica is hydrophilic and NR is hydrophobic. The usual method to overcome this issue is by adding coupling agent. In 1987 Wu and coworkers introduced admicellar polymerization where a thin polymeric film will be formed on the silica s surface. This process yields a thin film of polymer on the silica which can further enhance the adhesion between the surfaces of silica and rubber. The steps involved in admicellar polymerization are outlined in Scheme 7.7. In principle, a bilayer of surfactant, i.e. the admicelle, is first formed on the surface of the silica. Monomer will then penetrate the admicelle, i.e. the adsolubilization of monomer. Upon addition of initiator to the reaction system, in situ polymerization occurs in the admicelles. Finally, the surfactant is removed by washing with water and an ultrathin polymer layer is formed on the surface of the silica. The polymerization of the monomer in the admicelles can be induced by thermal process, chemical initiators or radiation. ... 

Another approach of chemical modification of silica for rubber nanocomposite for the same aim, i.e. to reduce the filler-filler interaction, is differential microemulsion polymerization. In general, the process involves two main continuous steps (i) pre-treatment/chemical bonding of silica particles with coupling agent, and (ii) polymerization of the monomer in a reaction medium containing the pre-treated silica. The resultant product is a core-shell structure where nano-silica is the core encapsulated by a nanopolymer shell. 

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