Polymer hydroxyl-containing

Boron also reacts with hydroxyl-containing polymers such as cellulose. When exposed to a flame the boron and hydroxyl groups form a glassy ester that coats the substrate and reduces polymer degradation. A similar type of action has been observed in the boron—alumina tfihydrate system. 

The diisopropoxy-bis-(triethanolamine)-titanate, TYZORTE [36673-16-2] is an excellent cross-linker for aqueous solutions of hydroxyl-containing polymers. The reaction product of TYZORTPT with a mixture of trialkano1 amines and dialkanolarnines or monoalkano1 amines can be used to cure polyester-based powder coatings (109). Other ligands of this type iaclude triisopropano1 amine [122-20-3] ... 

A similar type of condensation between a hydroxyl-containing polymer (such as secondary cellulose acetate) with VO(BrC6H4N=CHO CfiH4)2 CUVOL2CI] produces photoactive polymers [68]. When irradiated with UV light in the presence of styrene or MMA, grafted and crosslinked polymers were obtained ... 

Hydroxyl containing polymers may be cross-linked with diisocyanates. Fordyce and Ferry cross-linked styrene-maleic anhydride copolymers through the action of glycols. The copolymerization of divinyl with vinyl monomers may be looked upon as a method of cross-linking chain polymers. The cross-linkages are introduced simultaneously with the growth of the linear polymer chains, rather than afterwards, but this difference is secondary. 

Redox initiation is often an efficient method for graft polymerization. Hydroxyl-containing polymers such as cellulose and poly(vinyl alcohol) undergo redox reaction with ceric ion or other oxidizing agents to form polymer radicals capable of initiating polymerization... 

Hydroxyl groups may also be introduced in the polymer by graft-copolymerization of hydroxyethyl methacrylate or glycidyl methacrylate, the latter being subsequently hydrolyzed 91). Heparin was immobilized on such hydroxyl-containing polymers by means of glutaric dialdehyde. The maximal amount of polymer-bound heparin was 80 ng/cm2. 

A perspective method for the production of HCP was proposed by Labarre et al 92-94) [t invo]ves radical graft-copolymerization of methyl methacrylate onto heparin effected by cerium salts (Ce4+). As well as other hydroxyl-containing polymers, heparin may react with cerium ions producing free radicals which may initiate graft-copolymerization of unsaturated compounds ... 

Monomeric metallochelates can also be immobilized on the polymer surface via a valent metal-carbon bonding. For example, the interaction of a copolymer of St and chloromethylstyrene with cobaloxime in a benzene-pyridine mixture gives PCMU with a Co—C bond [109]. N202-Metallochelates such as Co(II) complex with V,lV -bis(salicylaldehyde)ethylenediamine react with poly (chloromethylstyrene) (PCMSt) in THF at 193 K in a similar fashion [110], The same is true of reactions of quinoline (HQ) V(V) complexes with hydroxyl-containing polymers [111] ... 

The product can be cross-linked with hydroxyl-containing polymers ... 

The evolution of HBr in the bromination reactions and the uptake of one bromine atom per ring indicate substitution at a secondary allylic carbon atom. The ease of oxidation and cross linking of the polymers and the presence of hydroxyl groups imply the intermediate formation of hydroperoxides on allylic carbon atoms. Treatment of the hydroxyl-containing polymer with benzoyl chloride indicates that the bulk of the hydroxyl groups are on secondary carbon atoms, since tertiary hydroxyl groups would tend to be replaced by chlorine. Although these results do not permit the elimination of structure B, it appears that the bulk of the structural units in the polycyclopentadiene corresponds to 1,2- addition (A). 

These three hydroxyl-containing polymers make up a three-dimensional polymer composite with a solid phase (cell wall) and voids (lumens) (Figure 2). The lumens can be viewed as bulk storage reservoirs for chemicals. For example, the void volume of southern pine springwood or earlywood with a density of... 

Since they are hydroxyl-containing polymers, cellulose ethers and possibly esters can be reacted covalently with many species, both mono- and polyfunctional, in order to stabilize and insolubilize their structure. The inter-molecular reactions include [23] ... 

GAR Garay, M.T., Rodriguez, M., Vilas, J.L., and Leon, L.M., Study of polymer-polymer complexes of poly(A-isopropylaciylamide) with hydroxyl-containing polymers, J. Macromol. Sci. PartB-Phys., 43, 437, 2004. 

The structure and chemical makeup of natural fibers varies greatly and depends on the source and many processing variables. However, some generalizations are possible. Natural fibers are complex, three-dimensional, polymer composites made up primarily of cellulose, hemicellulose, pectins, and lignin [12]. These hydroxyl-containing polymers are distributed throughout the fiber wall. The major chemical components of selected natural fibers are listed in Table 11.1. 

In the synthesis of polymers with functional groups suitable for drug attachments, hydrophilic hydroxyl-containing polymers and copolymers of divinyl ether and maleic anhydride are commonly used as precursor backbones for further modification. Polyfvinyl alcohol) has also been used in this way, both as the starting point for enzyme immobilization work, sometimes via azido group reactions, and also as a precursor for new membranes of potential interest in the haemodialysis field. ... 

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