Alicyclic monomers

The cyclopentane-type dianhydride CpDA was synthesized by thermal dehydration of c/s,c/s,cw,ds-l,2,3,4-cyclopentanetetracarboxylic acid at 170-190 °C. The norbomane-type dianhydride BHDA was prepared from endo-nadic acid via three steps.[5] The H-NMR spectrum revealed that BHDA consisted of the two isomers, bicyclo[2.2.1]heptane-2-emfo,3-era/o,5-exo,6-ejco-tetracarboxylic dianhydride and the all-exo derivative. The ratio was estimated to be 1 1 from the spectrum. The structures and abbreviations of alicyclic monomers are illustrated in Figure 1. 

Scheme 7.36 Synthetic scheme for the polymerization of norbornene and its derivatives via free radical polymerization (FRP), ring-opening metathesis polymerization (ROMP), and vinyl addition polymerization (VAP) techniques. Polymers I, II, and III are isomers that differ in their enchainment and physical properties. Co- and terpolymerization of norbornene and derivatives of norbornene with other alicyclic monomers such as maleic anhydride, methyltetracyclododecene carboxylic acid, etc. are also successfully synthesized with this scheme. (Note that 2, 3- and 2,7-enchainments of repeating units are reported in type I polymers. °°)...

Scheme 7.38 Free radical copolymerization of various alicyclic monomers initiated by (1) azoisobutyronitrile (AIBN) in THF, and (2) di-tert-butyl peroxide (DTBP) in propylene glycol monomethylether acetate, and used in the synthesis of the alicyclic polymer resist materials for ArF lithography, pioneered at the University of Texas at Austin in 1995. Note that although only 2,3-enchainment of the cyclic olefins is shown above the scheme, 2,7-enchainement is also possible, as reported by Gaylord and co-workers. ...

Scheme 7.39 Ring-opening metathesis polymerization of various alicyclic monomers using K2lrCl6- Following polymerization, the polymer was hydrogenated with diimide produced in situ.

Alternative monomers for elimination of crystallinity in PET have been recently proposed. In each of these cases, cyclic monomers were employed, and in most cases, these monomers were alicyclic, and potentially possess sub-7 g molecular motions that could also be of help in dissipating impact energy through molecular motions. The four-membered ring monomer, 2,2,4,4-tetramethyl-l,3-cyclobutanediol (CBDO), first developed by the Shell Chemical Company, has... 

Aliphatic and alicyclic amines form one of the most extensively used categories of compounds in a variety of manufacturing industries. These compounds are first-phase materials for chemical synthesis, intermediates, pharmaceuticals, pesticides, soil sterilizers, and several kinds of solvents, rubber products, rocket propellants, and plastic monomers. This chapter discusses the safety and toxicity of selected compounds handled by workers in different industries. More information and extensive literature are available in several study reports on members of this important group.31,32... 

Many aliphatic and alicyclic nitrones have been reported to give dimers thus 2,4,4-trimethyl-1-pyrroline-l-oxide dimerized, on standing, to 88 by the nucleophilic addition of a 2-methyl group of the monomer across the C=N bond of another molecule (the chemistry of nitrones has been reviewed by Delpierre and Lamchen110). Oxidation of 1-hydroxypiperidine does not give the expected cyclic nitrone but a product to which the dimeric structure 89 has been assigned.111... 

Cyclohexene oxide is useful as a monomer in polymerization and the coating industry. It is used in the synthesis of alicyclic molecules used in pesticides, pharmaceuticals, perfumery, and dyestuffs, and as a monomer in polymerization with CO2... 

Figure 17.9 The chemistry of the CARL process scheme. x may stand for hydroxystyrene, acrylates, and alicyclic monomeric units, etc. R represents an alkyl group. Structure (I) is the alkaline-insoluble resist resin, consisting of an alternating polymer of maleic anhydride and an appropriate monomer. Structure (II) is the product of the base-catalyzed hydrolysis of the anhydride resin. Structure (III) is the bis-diaminoalkyl-oligo-dimethylsiloxane, the CARL process silylating agent. Structure (IV) is the cross-linked product of silylating agent and the hydrolyzed anhydride resist resin.

Ionized gels were acrylic acid-sodium acrylate copolymers. The samples were provided by Norsolor Company. The gels were obtained through an inverse suspension process. In this technique, the aqueous phase, containing an hydrophilic monomer, was dispersed in an organic phase, such as an alicyclic or aliphatic hydrocarbon. 

When highly basic diamines are used, e.g., alicyclic diamines are used as a diamine monomer, a salt is produced by the neutralization reaction before forming a poly(amic acid) at the point that the alicyclic diamines are mixed with acid dianhydrides and precipitated. Since this salt is in a stable state, it is neither possible to form a poly(amic acid) by polymerization reaction nor to imidize poly(amic acid) by the reaction with a hydrating reagent [27]. 

The functionalisation of hydrocarbon feedstocks is a key value-creating step in the chemical industry. Selective oxidation reactions, such as the epoxidation of alkenes, are a substantial basis of fine chemical production [98]. For example, propylene oxide is used industrially in the production of polyurethane and propylene glycol [99], ethylene oxide (EO) is used to produce ethylene glycol and various ethoxylates [100], while cyclohexene oxide is used as an alicyclic chemical intermediate in the production of pesticides, pharmaceuticals, perfumes and dyes [101] or as a monomer in photoreactive polymerisation [102]. 

When unsaturated fatty acids are subjected to thermolytic cleavage, dimers, polymers and cyclic compounds are produced. The dimers include alicyclic mono-, di-, and triene dehydrodimers, saturated dimers with cyclopentene structures, tetrasubstituted cyclohexanes and bicyclic and tricyclic dimers (Nawar, 1985). Cyclic mononmers exhibit toxicity in experimental animals (Van Gastel et al, 1984), therefore, generation of cyclic monomers at high temperature frying with oils containing polyunsaturated fatty acids should be carefully monitored. 

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