Lignin copolymer

TABLE 10. Elemental Assay, Percent Hydrolysis, and Limiting Viscosity lumber for Partially Hydrolysed Lignin Copolymer -... 

The similarities in the structure and 3neld of the acids obtained by this degradation from natural spruce lignin and a biosynthetic "spruce lignin copolymer (mixed DHP) made in vitro from a mixture of the three -coumaryl alcohols established the general identity of the two preparations 46, 47). 

S. S. Kelley, Incorporation of lignin copolymers into polyurethane materials, Ph.D. thesis, Virginia Polytech. Inst. State Univ., 1987, Univ. Microfilms Int., DA8814587. 

Polyol Functionality in Relation to Method of Preparation--Ratio of Lignin Copolymer to Propylene Oxide (All Reactions 4 hrs. reaction time temperature 200-250°C)... 

Lignin Preparation Ratio of Propylene Oxide to Lignin Copolymer Catalyst System A1 B2 on Number COOH Number... 

From the above results, it is confirmed that LS can be reacted with CL in a similar way to other types of lignin, such as KL and alcoholysis lignin. It is thought that process ability of lignins will be attained by introduction of hydrophobic side chains such as PCL to lignin. Copolymers obtained are expected to have biocompatibility since both lignin and PCL are biocompatible. 

Alkaline methanolysis of graft vinyl acetate-lignin copolymers (Samples LVAO, LVAl, and LVA60) led to the corresponding water-soluble vinyl alcohol copolymers, whose lignin content, as determined by the absorption at 280 nm, resulted to be substantially higher than in the parent VAc copolymer samples hydrolyzed samples, respectively, thus demonstrating however the formation of copolymer macromolecules. 

Acrylamide graft copolymers such as those with starch (qv)(131), dextran (132), and lignin (qv) (133), have been studied to try to reduce copolymer costs. A general disadvantage of acrylamide copolymers is greater cost compared to partially hydroly2ed polyacrylamides. 

This multitude of properties the polymer must possess dictate that better polymer performance will be obtained from materials with complicated structures. Such polymers are complex polymers l) random copolymers, 2) block copolymers, 3) graft copolymers, 4) micellizing copolymers, and 5) network copolymers. There has been a dramatic increase in the past decade in the number and complexity of these copolymers and a sizable number of these new products have been made from natural products. The synthesis, analysis, and testing of lignin and starch, natural product copolymers, with particular emphasis on graft copolymers designed for enhanced oil recovery, will be presented. 

GRAFT COPOLYMERS. Goggarty was one of the first applications specialists to propose, in 1978, that graft copolymers by used for resource recovery(34) A number of such graft copolymers have now been made and tested and the knowledge gained about products based on lignin and starch will be summarized below. 

A Cationic Graft Copolymer of Lignin. The applications of the anionic graft copolymers described above are many but the negative charge on the polymer or the behavior of the anionic polymer under application conditions often limit the utility of these materials. 

One solution to this problem is to create new copolymers of lignin which have the appropriate functional groups to perform effectively in a given environment. One such class of new materials with the right parts to function where anionics fail is the class of cationic polymers. Data from such a copolymer will now be presented. 

Lignin has been reacted with 4N,4N - dimethyl-4-ammoniumhept-1,6 -diene chloride monomer to make a cationic graft copolymer. The structure of the copolymer is illustrated by the formula ... 

The composition, reaction conditions, and yield of copolymer-1 (24-37 series ) are shown in Table 12. The content of 4N,4N-dimethyl-4-ammoniumhept-1,6-diene chloride in the reaction ranges from 0 to 30 molar percent of total monomer content. The concentration of lignin, calcium chloride, and monomer in the... 

Table 12 Synthesis data of cationic lignin-graft copolymer ( lignin-g-2-propenamide-DMDAC )...

Table 13 The composition of Reaction Mixture Used to Make Lignin Graft Copolymers...

J.J. Meister, Review of the Synthesis, Characterization, and Testing of Graft Copolymers of Lignin, p.305-322 of Renewable-Resource Materials New Polymer Sources, C.E. Carraher,... 

Solution prepregging, 20 284-285 Solution processing, 14 80 Solution process, of ethylene-propylene polymer manufacture, 10 708-710 Solution properties of lignin, 15 13 of polyampholytes, 20 479 ofVDC copolymers, 25 703-706 Solution spectrophotometry, 9 232 Solution spinning... 

Chen, M.-J., Meister, J.J., Gunnells, D.W. and Gardner, D.J. (1995). Alteration of the surface energy of wood using lignin-(-l-phenylethene) graft copolymers. Journal of Wood Chemistry and Technology, 15(2), 287-302. 

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