Polymer nanocomposites polyimide

Polyimide-clay nanocomposites constitute another example of the synthesis of nanocomposite from polymer solution [70-76]. Polyimide-clay nanocomposite films were produced via polymerization of 4,4 -diaminodiphenyl ether and pyromellitic dianhydride in dimethylacetamide (DMAC) solvent, followed by mixing of the poly(amic acid) solution with organoclay dispersed in DMAC. Synthetic mica and MMT produced primarily exfoliated nanocomposites, while saponite and hectorite led to only monolayer intercalation in the clay galleries [71]. Dramatic improvements in barrier properties, thermal stability, and modulus were observed for these nanocomposites. Polyimide-clay nanocomposites containing only a small fraction of clay exhibited a several-fold reduction in the... 

Thermoset polymers like polyimide, crosslinked sulfonated poly(ether ether ketone) and polyacrylate can be used for membrane applications. The presence of nanoparticle nucleates the nanopore formation with the assistance of an agent. The nanopore is responsible for the solvent separation and transportation. Membranes such as solvent filters, filters for bacteria and virus, and membrane for gas separation can be developed using clay-polymer nanocomposites [118-119]. 

Dielectric constant data have been reported on several unreinforced polymers, including polyimides [19-21], silicones [22], epoxy resins [23], polyurethanes [23], polyaniline nanofibers [16, 17], zirconium nanocomposites [24], cross-linked polyethylene [15], low-density polyethylene [22], doped polyimines [19], polyimide-3-zirconium propoxide nanocomposites [24], poly linu-naphthyl ether [30], and cross-linked polyethylene-polyethylene polyacrylate acid blends [15]. 

Successful commercialization of low cost, high efficiency solar cell fabrication is highly dependent on fabrication methods that employ continuous processing techniques. One major issue encountered in solar cell construction is the adhesion of thin film solar cells on polyimide substrates. Another involves the adhesion between polymer nanocomposite solar cell structures. The examination of the adhesion promotion potential of variable chemistry atmospheric plasma surface modifications against wet primer chemistry in solar cell construction has shown that APT is a viable continuous and environmentally friendly processing alternative to batch plasma and surfactant-based surface modification protocols. 

Moreover, in situ polymerization is the only way to prepare thermoset polymer nanocomposites because a thermoset polymer can be neither melted nor dissolved. The first thermoset polymer-LDH nanocomposite was reported by Hsueh and Chen, which was prepared from a mixture of aminobenzoate-modified MgAl-LDH and polyamic acid (polyimide precursor) in A,A-dime-thylacetamide. In a similar way, epoxy-LDH nanocomposites were also obtained. 

Chang J-H and Park K M, Polyimide nanocomposites comparison of their properties with precursor polymer nanocomposites , Polym. Eng. Sci., 2001 41(12) 2226-30. 

This can be performed by co-condensation of monomer and precursor vapors. The main advantages of this mediod are a high homogeneity and a strong polymer-particle binding. It is frequently used for nanocomposites of metals in polyamides, polyimides, polystyrene or Teflon. Co-condensation at low temperature in combination with gamma or UV irradiation yield metal-polymer nanocomposites of variable partiele size and high partiele density. 

Liang, Z.-M., Yin, J., and Xu, H. J. Polyimide/montmorillonite nanocomposites based on thermally stable, rigid-rod aromatic amine modifies, Polymer (2003), 44, 1391-1399. 

Tsai MH, Whang WT (2002) Low Dielectric Polyimide/Poly(silsesquioxane)-Like Nanocomposite Material, Polymer 42(9) 4197—4207... 

Polymeric nanocomposites are a class of relatively new materials with ample potential applications. Products with commercial applications appeared during the last decade [1], and much industrial and academic interest has been created. Reports on the manufacture of nanocomposites include those made with polyamides [2-5], polyolefins [6-9], polystyrene (PS) and PS copolymers [10, 11], ethylene vinyl alcohol [12-15], acrylics [16-18], polyesters [19, 20], polycarbonate [21, 22], liquid crystalline polymers [8, 23-25], fluoropolymers [26-28], thermoset resins [29-31], polyurethanes [32-37], ethylene-propylene oxide [38], vinyl carbazole [39, 40], polydiacethylene [41], and polyimides (Pis) [42], among others. 

Yani, Y., and Lamm, M. H. 2009. Molecular dynamics simulation of mixed matrix nanocomposites containing polyimide and polyhedral oligometric silsesquiox-ane (ROSS). Polymer 50 1324-1332. 

The quantity of the hterature in the field of the nanocomposite polymeric materials has grown multiple times in recent years. The possibility to use almost all polymeric and polycondensated materials as a matrix is shown The nanocomposites from various organoclays and polymers have been synthesized. Here is just a small part of the compounds for being the matrix referenced in literature polyacrylate [83], polyamides [82,84,85], polybenzoxazine [86], polybutylene terephtalate [11,82,87], polyimides [88], polycarbonate [89], polymethylmetaciylate [90], polypropylene [91,92], poly-... 

Kovalev MK, Kalinina E, Androsov DA, Cho C. Synthesis of transparent and thermally stable polyimide-aramid nanocomposites -prospective materials for high-temperature electronic manufacture applications. Polymer 2013 54(l) 127-33. 

I. Gofman, B. Zhang, W. Zang, Y. Zhang, G. Song, C. Chen, et al.. Specific features of creep and tribological behavior of polyimide-carbon nanotubes nanocomposite films Effect of the nanotubes functionalisation. Journal of Polymer Research, 20 (10), 1-9, 2013. 

Commercial membranes for CO2 removal are polymer based, and the materials of choice are cellulose acetate, polyimides, polyamides, polysulfone, polycarbonates, and polyeth-erimide [12]. The most tested and used material is cellulose acetate, although polyimide has also some potential in certain CO2 removal applications. The properties of polyimides and other polymers can be modified to enhance the performance of the membrane. For instance, polyimide membranes were initially used for hydrogen recovery, but they were then modified for CO2 removal [13]. Cellulose acetate membranes were initially developed for reverse osmosis [14], and now they are the most popular CO2 removal membrane. To overcome state-of-the-art membranes for CO2 separation, new polymers, copolymers, block copolymers, blends and nanocomposites (mixed matrix membranes) have been developed [15-22]. However, many of them have failed during application because of different reasons (expensive materials, weak mechanical and chemical stability, etc.). 

Polyimides are probably the most appropriate dass of polymers for the production of bicontinuous nanocomposites, in so far as they represent types of polymers that have been widely used in applications requiring stringent performance at high temperatures. The incorporation of continuous silica domains, therefore, is expected to enhance the high-temperature properties to bridge the gap between polymers and... 

Common solvent technique is based on a solvent system in which the polymer or pre-polymer is soluble and the silicate layers are swellable. The layered silicate is first swollen in a solvent, such as water, chloroform, or toluene. When the polymer and layered silicate solutions are mixed, the polymer chains intercalate and displace the solvent within the interlayer of the silicate. Upon solvent removal, the intercalated structure remains, resulting in the formation of PCN. Polyimide based nanocomposites are made by using a common solvent like dimethyl acetamide (DMAc) [22],... 

Mo T-C, Wang H-W, Chen S-Y, Dong R-X, Kuo C-H, Yeh Y-C (2007) Synthesis and characterization of polyimide-silica nanocomposites using novel fluorine-modified silica nanoparticles. J Appl Polym Sci 104(2) 882-8W... 

Tang JC, Lin GL, Yang HC, Jiang GJ, Chen-Yang YW (2007) Polyimide-silica nanocomposites exhibiting low thermal expansirai coefficient and water absorption from surface-modified silica. J Appl Polym Sci 104(6) 4096-4105... 

Tang JC, Yang HC, Chen SY, Chen-Yang YW (2007) Preparation and properties of polyimide/silica hybrid nanocomposites. Polymer Compos 28(5) 575—581... 

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