Hemicellulose, the second, most common polysaccharide in nature constitutes approximately 20—35% of lignocellulosic biomass. Effective utilization of biomass, hitherto underutilized, is gaining tremendous importance for the production of energy, fuels, and chemicals. Amongst the vast array of chemicals derived from lignocellulosics, furfural is the key chemical that finds wide applications in oil refining, plastics, pharmaceutical and agrochemical industries. There is no synthetic route for the production of furfural. A few conventional technologies currently in practice for its separation and subsequent isolation are appropriately reviewed. Major disadvantages associated with processes currently used for the production of furfural based on acid-catalyzed hydrolysis have been discussed. A need to develop a process which is devoid of all the shortcomings associated with conventional process is emphasized. Several important aspects of chemistry underlying the acid hydrolysis of xylose are discussed. The importance of myriad pre-treatment steps involved to surmount the physical and chemical barriers and to liberate xylose from the confines of acid-resistant layer of lignin has been emphasized. New developments in the production of furfural from cyclodehydration of xylose using solid acid catalysts in the recent past have been reviewed appropriately in present communication. Finally, the production of furfural and furfuryl alcohol, their domestic market and export in China deserve some coverage and therefore have appropriately been discussed as well. © 2008 Society of Chemical Industry and John Wiley & Sons, Ltd

Furfural: Hemicellulose/xylosederived biochemical

Biomass represents an abundant and relatively low cost carbon resource that can be utilized to produce platform chemicals such as levulinic acid. Current processing technology limits the cost-effective production of levulinic acid in commercial quantities from biomass. The key to improving the yield and efficiency of levulinic acid production from biomass lies in the ability to optimize and isolate the intermediate products at each step of the reaction pathway and reduce re-polymerization and side reactions. New technologies (including the use of microwave irradiation and ionic liquids) and the development of highly selective catalysts would provide the necessary step change for the optimization of key reactions. A processing environment that allows the use of biphasic systems and/or continuous extraction of products would increase reaction rates, yields and product quality. This review outlines the chemistry of levulinic acid synthesis and discusses current and potential technologies for producing levulinic acid from lignocellulosics. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd

The conversion of lignocellulosics to levulinic acid

A polymer compound comprising a repeating unit represented by formula (1) and a repeating unit represented by formula (2), wherein, Ar1, Ar2 and Ar6 each independently represent an arylene group, a divalent heterocyclic compound group, etc.; Ar3 is an arylene group, arylene vinylene group, or a divalent heterocyclic compound group; Ar4 and Ar5 are each independently an aryl group or a monovalent heterocyclic compound group. The polymer compound has excellent characteristics of strong fluorescence and large charge transporting property.

Polymer Compound And Polymer Light-Emitting Device Using The Same

PROBLEM TO BE SOLVED: To provide a new polymer compound having high emission intensity. SOLUTION: The polymer compound comprises a repeating unit represented by formula (1) or (2) [(in formula 1, Ar 1 and Ar 2 are each a trivalent aromatic hydrocarbon group or trivalent heterocyclic group; X 1 and X 2 are each O, S, C(=O) or the like excluding the case that X 1 and X 2 are the same; X 1 and Ar 2 bond to adjoining carbon atoms in the aromatic ring of Ar 1 , and X 2 and Ar 1 bond to adjoining carbon atoms in the aromatic ring of Ar 2 ) and (in formula 2, Ar 3 and Ar 4 are each a trivalent aromatic hydrocarbon group or trivalent heterocyclic group; X 3 and X 4 are each N, B, P or the like excluding the case that X 3 and X 4 are the same; X 3 and Ar 4 bond to adjoining carbon atoms in the aromatic ring of Ar 3 , and X 4 and Ar 3 bond to adjoining carbon atoms in the aromatic ring of Ar 4 )]. COPYRIGHT: (C)2004,JPO

Polymer compound and polymer light-emitting element using the same

High purity epoxide compounds, methods for preparing the high purity epoxide compounds, and compositions derived from the epoxide compounds are provided. Also provided are materials and articles derived from the epoxide compounds.

High heat monomers and methods of use thereof

Benzocyclobutene-based polymers for microelectronics

A compound having at least one 2-hydroxy-1,3-propylidene, 2-acetoxy-1,3-propylidene, or 2-alkoxy-1,3-propylidene moiety between two benzocyclobutene end moieties is prepared by (a) contacting a diepoxide species with a benzocyclobutene species containing a functionality capable of reacting with an epoxy group, (b) contacting an epoxy-containing benzocyclobutene species with a species containing two functionalities capable of reacting with an epoxy group, (c) contacting an epoxy-containing benzocyclobutene species with a benzocyclobutene species containing a functionality capable of reacting with an epoxy group, (d) contacting epichlorohydrin with benzocyclobutene species capable of reacting with an epoxy group, or (e) contacting epihalohydrin with benzocyclobutene species and difunctional species, wherein both species contain functionalities capable of reacting with epoxy groups. Each benzocyclobutene moiety is attached to the 2-hydroxy-1,3-propylidene moiety at the six-membered ring through oxygen or sulfur atoms, carboxyl, N-alkylimino, or 1,3-dioxyphenylene units. The unit linking the two benzocyclobutene moieties optionally contains aromatic moieties. The polymers prepared from the compounds are suitable for use in composites, coatings, adhesives, and binders. The polymers have outstanding processability and are mainly non-crystalline materials with low melt viscosities prior to the onset of curing.

Bisbenzocyclobutene thermosetting compounds and process for preparing the same

This invention relates to a solvent process for the conversion of aromatic propargyl ethers into chromenes The process can be catalyzed with copper or zinc salts The preferred salt is cuprous chloride The most preferred solvent is a dichlorobenzene The invention also relates to chromene products formed using the process and to the polymerization of that chromene product and its polymerized product, the latter product having substantially improved flexural modulus and flexural strength properties The polymerized product is also moisture insensitive

Polymer resulting from the cure of a preformed chromene-containing mixture

A novolac resin is prepared by reacting a phenolic compound, an aldehyde or a ketone, and a hydroxyl-substituted benzocyclobutene compound wherein the hydroxyl group is attached to an aromatic ring. The benzocyclobutenes are connected to the phenolic rings through an oxygen or oxyaryl bridge, or the cyclobutene is fused directly to a phenol ring. The novolac resin cures without evolution of volatiles and, when cured, provides a polymer which has a high glass transition temperature and which is essentially insoluble in organic solvents.

Daniel M. Scheck

Papers

Benzocyclobutene-based polymers for microelectronics

Bisbenzocyclobutene thermosetting compounds and process for preparing the same

Polymer resulting from the cure of a preformed chromene-containing mixture

Benzocyclobutene novolac resin compositions