Polyimide-Nylon 6 copolymers

Polyimide—Nylon 6 Copolymers Single-Component Molecular Composites... 

Scheme 1. Approaches to novel polyimide-g-nylon 6 and nylon 6- polyimide- nylon 6 copolymers.

Typical Procedure for the Preparation of the Polyimide- -Nylon 6 Copolymers. 

Impact Polystyrene Nylon 12 Nylon 612 Polyimide SAN Copolymer... 

There are numerous bifunctional monomers used in condensation polymerization. Some of the more popular signature groups that turn up frequently are shown in Figure 22-3. Important copolymers made by condensation include epoxies, nylon, polyesters, polycarbonate, and polyimides. As always, there are exceptions, and one is Nylon 6 made by a ring opening reaction of caprolactam. All of these will be covered in the next two chapters. 

Layered clay nano composites have been prepared by melt intercalation for a variety of polymers, including polystyrene [221], nylon-6 [222], ethylene-vinyl acetate copolymers [223], polypropylene [224], polyimide [225], poly(styrene-fo-butadiene) [226], and PEO [227],... 

Chem. Descrip. N-Methyl pyrrolidone CAS 872-50-4 EINECS/ELINCS 212-828-1 Uses Solvent, cosolvent In coatings, stripping/cleaning of paints/vamishes. Industrial cleaning, mold cleaning, petrochem. processing solvent for adhesives, inks, dyes, soaps, metal complexes, agric. solvent for PVAc, PVDF, PS, vinyl copolymers, nylon and aromatic polyamides and polyimides, polyesters, acrylics, PC, cellulose derivs., syn. elastomers, waxes... 

Chuah H H, Kyu T and Helminiak T E (1989) Scaling analysis in the phase separation of poly(j> phenylene benzobisthiazole)/Nylon-66 rigid-rod molecular composites, Polymer 30 1591-1595. Chang K Y, Chang H M and Lee Y D (1994) Molecular composites. 2. Novel block copolymer and semi-interpenetrating polymer network of rigid polyamide and flexible polyamide polyimide, J Polym Sci Part A Polym Chem 32 2629-2639. 

DMA has been applied to the determination of Tg in neoprene, styrene-butadiene, polyisoprene, polybutadiene, polychloroprene, nitrile ethylene-propylene-diene, and butyl rubbers [4], polybutadiene [10], glass-filled low-density polyethylene [11], PU, PMMA, polyimides, acrylonitrile-butadiene-styrene terpolymer, PET, and Nylon 6 [2], bisphenol-A epoxy diacrylate, N-vinyl pyrrolidone copolymer, and trimetholpropane triacrylate [5]. 

Characterization. The different solubilities of the graft and block copolymers, compared to their homopolymer components, were the first indicaton of the formation of copolymers rather than homopolymer blends. Nylon 6 and the polyfunctional polyimides were soluble in formic acid and NMP, respectively. However, the graft and block copolymers were not soluble in formic acid or NMP. They were only soluble in m-cresol, indicating an enhanced chemical resistance compared to nylon 6. 

The graft and block copolymer samples were successively extracted with methanol, NMP and formic acid to determine the amounts of residual caprolactam, unreacted polyimides and nylon 6 homopolymer present The residual caprolactam in the final products was less than 3 wt% and no nylon 6 homopolymer was detected. 

Novel polyimide-g-nylon 6 and nylon 6- polyiniide-] nylon 6 copolymers were synthesized by polycondensation and subsequent anionic, ring-opening polymerization methods. The graft and triblock copolymer structures were characterized with FTIR, GPC, selective extractions, DSC,TGA, tensile test and DMA. The effective reinforcement of nylon 6 with the incorporation of only a few wt% polyimide was demonstrated by the sigmOcant improvements in the copolymers thermal and mechanical properties, and chemical resistance. 

Ding. H, Ph. D. Dissertation, Synthesis and Characterization of Novel Polyimid-g-Nylon 6 and Nylon 6-b-Polyimide-b-Nylon 6 Copolymers, The University of Akron, 1994. 

Until 2003, Chen s [28], Qu s [29-31], and Hu s [32] groups independently reported nanocomposites with polymeric matrices for the first time the. In Hsueh and Chen s work, exfoUated polyimide/LDH was prepared by in situ polymerization of a mixture of aminobenzoate-modified Mg-Al LDH and polyamic acid (polyimide precursor) in N,N-dimethylactamide [28]. In other work, Chen and Qu successfully synthesized exfoliated polyethylene-g-maleic anhydride (PE-g-MA)/LDH nanocomposites by refluxing in a nonpolar xylene solution of PE-g-MA [29,30]. Then, Li et al. prepared polyfmethyl methacrylate) (PMMA)/MgAl LDH by exfoliation/adsorption with acetone as cosolvent [32]. Since then, polymer/LDH nanocomposites have attracted extensive interest. The wide variety of polymers used for nanocomposite preparation include polyethylene (PE) [29, 30, 33 9], polystyrene (PS) [48, 50-58], poly(propylene carbonate) [59], poly(3-hydroxybutyrate) [60-62], poly(vinyl chloride) [63], syndiotactic polystyrene [64], polyurethane [65], poly[(3-hydroxybutyrate)-co-(3-hydroxyvalerate)] [66], polypropylene (PP) [48, 67-70], nylon 6 [9,71,72], ethylene vinyl acetate copolymer (EVA) [73-77], poly(L-lactide) [78], poly(ethylene terephthalate) [79, 80], poly(caprolactone) [81], poly(p-dioxanone) [82], poly(vinyl alcohol) [83], PMMA [32,47, 48, 57, 84-93], poly(2-hydroxyethyl methacrylate) [94], poly(styrene-co-methyl methacrylate) [95], polyimide [28], and epoxy [96-98]. These nanocomposites often exhibit enhanced mechanical, thermal, optical, and electrical properties and flame retardancy. Among them, the thermal properties and flame retardancy are the most interesting and will be discussed in the following sections. 

NYLON (INCLUDING AROMATICS) POLYIMIDES POLYAMIDE-IMIOES THERMOPLASTIC POLYESTERS (INCLUDING AROMATICS) POLYSULFONES POLYSTYRENE / COPOLYMERS (EXCEPT ABS)... 

The comparatively low impact strength of many well-known polymers, such as PMMA, polystyrene and PVC, led to the production of rubber-modified thermoplastics with high impact strength. The best-known examples are high-impact polystyrene (HIPS) and ABS copolymer, where the rubbery phase is dispersed throughout the polymer in the form of small aggregates or balls. Other polymers that have been toughened in this way include PMMA, PVC, polypropylene, polycarbonate, nylons and thermosets such as epoxies, polyesters and polyimides. 

Ding H and Harris F W (1995) Synthesis and characterization of a novel nylon 6-6-polyimide-6-nylon 6 copolymers, Pure Appl Chem 67 1997-2004. 

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