Poly -starch graft

Although they lack commercial importance, many other poly(vinyl acetal)s have been synthesized. These include acetals made from vinyl acetate copolymerized with ethylene (43—46), propjiene (47), isobutjiene (47), acrylonitrile (48), acrolein (49), acrylates (50,47), aHyl ether (51), divinyl ether (52), maleates (53,54), vinyl chloride (55), diaHyl phthalate (56), and starch (graft copolymer) (47). 

Dragunski, D. C. and PawHcka A. (2001). Preparation and characterization of starch Grafted with Toluene Poly (propylene oxide) diisocyanate. Mater. Res., 4, 77-81. 

Synthesis. Graft copolymer was formed in aqueous solution by ceric-ion-initiated, radical polymerization of monomer on starch. Polymerization was conducted in an inert, atmosphere. Details of the synthesis procedure may be found in references 41 to 43 In recovering the polymer product, freeze drying was used with care since freeze drying produces a more dissolvable and useful product but can degrade polymers with molecular weights of 1 million or more. Poly(starch-g-(1-amidoethylene)) Poly(starch-g-(1-amidoethylene))... 

Poly(starch-g-(l-amidoethylene)) copolymer is not a polyelectrolyte and will be a smaller molecule in water than an equal molecular weight, partially hydrolyzed poly(l-amidoethylene). Polyelectrolyte effect should, however, cause the graft copolymer to expand in solution in the same way it causes poly(l -amidoethylene) to expand, so a series of hydrolyzed graft copolymers were prepared from poly(starch-g-(l-amidoethylene))(41-43) and these derivatives were tested to determine the effect of hydrolysis on copolymer properties in solution. 

Base polymer Starch—graft copolymerization, carboxymethylation Cellulose—graft copolymerization, carboxymethylation Synthetic polymers—poly(acrylate), poly(vinyl alcohol), poly(acrylamide), poly(oxyethylene), cationic polymer... 

Avery creative application of the system HRP/H202/Acac for graft polymerization of acryl amide on starch was reported recently by Biswas and coworkers [39], Thus, a biocatalytic alternative route to the established cerium( IV)-based routes to poly(acrylate)-grafted starch with applications as superabsorbers [44] or performance additives in paper making [45] or textile sizing [46] was reported. Under non-optimized conditions grafting efficiencies of up to 65% are reported. The... 

General [13,16, 20, 22] Mediator-free [28] Various [i-di kelone mediators [25] Immobilized enzyme [38] Water in SCC02 polymerizations [19] Surfactants [21] Poly acrylamide starch graft polymers[39[. 

Figure 6.11 Proposed mechanism for the HRP-initiated poly(acrylamide)-grafting of starch [39].

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... 

Graft copolymers of starch with acrylonitrile and 2-acrylamido-2-methylpropanesulfonic acid, after saponification, were claimed to be good sorbents.3092 A composite of saponified acrylonitrile-starch-copolymer with vinyl formal polymers showed very good salt-rejection characteristics and served as membranes.3093 The same material prepared with poly(vinyl chloride) has been used in gaskets for concrete pipes.3057 Saponified acrylonitrile-starch graft copolymers blended with C12-C16 alcohols provided excellent water-retention characteristics.3094... 

In the context of this chapter, the use of thermoplastic starch in blends with thermoplastic resins is of the main interest. As shown in Table 16.11, several blends have been developed, e.g., with vinyl alcohol copolymers (EVAl), polyolefins, aliphatic polyesters such as poly-e-caprolactone (PCL) and its copolymers, or polymers of glycols (e.g., 1,4-butanediol) with succinic, sebacic, adipic, azelaic, decanoic or brassihc acids, PCL + PVC. Compatibilization is possible by amylose/EVAl V-type complexes, starch grafted polyesters, chain extenders like diisocyanates, epoxies, etc. [Bastioli et al., 1992, 1993]. 

Parvathy, PC. Jyothi, A. N. Synthesis, eharaeterization and swelling behaviour of superabsorbent polymers from eassava starch-graft-poly(aerylamide). Starch/Starke 64(3) 207-218 (2012). 

Graft copolymers of A and B monomers are named poly(A-g-B) or poly A-graft-poly B with the backbone polymer -(-A-), — mentioned before the branch polymer. Some examples are poly(ethylene-g-styrene) or polyethylene-grayi-polystyrene and starch-gro -poly(methylmetha-... 

Poly(caprolactone)-grafted ramie cellulose whiskers and PCL-grafted waxy maize starch nanocrystals by directly grafting the polymer on the surface of the nanoparticles with a coupling agent... 

Suda K, KanlayaM, Manit S (2002) Synthesis and property characterization of cassava starch grafted poly[acrylamide-co-(maleic acid)] superabsorbent via-y irradiation. Polymer 43 3915-3924 Tabi T, Kovacs JG (2007) Examination of injection molded thermoplastic maize starch. Express Polym Lett 1 804-809... 

Superabsorbent Polymers Superabsorbent polymers (SAP) are now commonly made from the polymerization of acrylic acid blended with sodium hydroxide in the presence of an initiator to form a poly-acrylic acid, sodium salt (sometimes referred to as cross-linked sodium polyacrylate). This polymer, such as polyacrylamide copolymer, ethylene maleic anhydride copolymer, cross-linked carboxy-methyl-cellulose, polyvinyl alcohol copolymers, cross-linked polyethylene oxide, and starch grafted copolymer of polyacrylonitrile to name a few. Superabsorbent polymers are made using one of two primary methods suspension polymerization or solution... 

Starch grafted poly(acrylonitrile) copol)mier Starch grafted poly(acrylamide)... 

Starch grafted poly(2-propenamide-co-2-propenoic acid) Poly(2-propenamide-co-2-propenoic acid) sodium salt... 

Starch-graft-poly(butylene succinate) H, C Graft 216... 

Starch-graft-poly(sodium acrylate) C Graft 217... 

Willett, J. L., Kontnis, M. A., O Brien, G. S., Fanta, G. F, Gordan, S. H. (1998J. Properties of starch-graft-poly(glycidyl methacrylateJ-PHBV composites./. App/. Polym. Sci., 70,1121-1127. 

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