Amidation graft copolymers

Grafting can also occur in the amide nitrogen, either through an anionic-type mechanism which is beheved to operate when ethylene oxide [75-21 -8] and similar copolymers are grafted to polyamides, or through a polycondensation mechanism when secondary amides are formed as graft copolymers (70). 

An anionic technique by indirect grafting was proposed for N-metallation of Nylon by Yamaguchi (153-155), in which alcali metals dissolved in liquid ammonia displace the amidic hydrogen atoms. Nylon derivatives and graft copolymers can be synthetized from the N-metallated Nylon (153). For ethylene oxide as grafting monomer, the metallated fibers were soaked in a tetrahydro-furan solution of the monomer, at 60° C (154). Methyl methacrylate is grafted on Nylon with a conversion over 90% by this technique (155). Other procedures involve the use of sodium methoxide in methanol solution and subsequent anionic graft copolymerization of acrylonitrile in a tetrahydrofuran solution (156). 

Thus, each molecule destroys more than one radical chain. A variety of analogues of higher molecular weight, often oligomeric polymers, is available commercially for use in fibers and films, where the one shown (see 13.11) might be too volatile.21 Another method that has been used to reduce volatility is to react a hindered piperidinol or aminopiperidine with a graft copolymer of maleic anhydride on polypropylene to form an ester and amide, respectively (13.12).22... 

Poly(amino acids)2892 and polypeptides2893 can also be grafted onto starch. Starch was first alkylated in the presence of lithium naphthalene, and then the alkoxy derivatives were reacted with /V-carboxy anhydrides. Poly(amide amines) were produced by reacting amines with dioic acids on starch and then crosslinking with epichlorohydrin or 1,2-dichloroethane 2894 Grafting of starch with a synthetic polymer chain, for instance, polystyryl carboxylate anions prepared by an anionic polymerization, can be carried out on a blend of starch and cellulose functionalized by sulfonation, mesylation, or tosylation. In this manner, cellulose-starch graft copolymers were prepared.2895... 

Block copolymers, graft copolymers, ladder polymers,... e.g., ether, ester, amide, urethane, sulfite,... 

Foaming with dry gases generated by the thermal decomposition of a dihydro-oxadiazinone + azodicarboxylic acid amide or ester PPE-polyolefin graft copolymer and NBR Epoxy-terminated liquid PB, with either PP-MA or SEBS SBR and SBS copolymer ABS and SAN Hydroxynaphthoic acid... 

Table 5.8. Graft copolymer formation in binary PA/PO blends by amide-ester exchange...

The synthesis of core-shell magnetic nanoparticles from polyacrylic acid (PAA) graft copolymers containing side chains of PEO and PPO (Fig. 5) was demonstrated by Hatton et al. [102]. Using a mixture of the polymers at a temperature of 180°C, amine-terminated PEO and PPO were coupled onto the PAA via amidation. Super-paramagnetic polymer-coated nanoparticles were synthesized by the hydrolysis and condensation of Fe(II) and Fe(III) chloride salts in the presence of PPO- or PEO-modified PAA copolymers. The extraction of organic compounds from aqueous media towards the copolymer shell of hydrophobic PPO segments can be applied in the field of water purification. 

Styryl amylose amide (VAA) was prepared from maltopentose-substituted styrene (VM5A) by phosphorylase-catalyzed pol3unerization of glucose-1-phosphate (Glu-lP) (118) (Fig. 8). Subsequent radical copolymerization with acrylamide gave the corresponding graft copolymers.. 

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