Unsaturated polyesters derivative

Zhang and co-workers developed unique crosslinkable unsaturated polyesters by a one-pot lipase-catalysed oxidation followed by copolymerisation of crude linoleic acid, glycerol and l,18-ds-9-octanedecenedioic acid [81]. In a similar approach, Roumanet and co-workers prepared aliphatic unsaturated polyesters derived from l,18-(Z)-octadec-9-enedioic acid (a derivative of fatty acids from sunflower oil) and aliphatic diols of different molecular weight [82]. The double bonds of the ensuing polyester backbones were then epoxidised and photocrosslinked, yielding transparent and homogeneous crosslinked films with high hydrophobicity. 

Maleic anhydride itself has few, if any, consumer uses but its derivatives are of significant commercial interest (161). The distribution of end uses for maleic anhydride is presented in Table 9 for the year 1992 (182). The majority of the maleic anhydride produced is used in unsaturated polyester resin (see Polyesters, unsaturated). Unsaturated polyester resin is then used in both glass-reinforced appHcations and in unreinforced appHcations as shown in Table 10 (183). 

Propylene glycol, i.e., 1,2-propanediol (1,2-PDO), is an important commodity chemical. It is used as biodegradable functional fluids and as precursors for the syntheses of unsaturated polyester resins and pharmaceuticals (9-10). Propylene glycol is currently produced from petroleum-derived propylene via oxidation to propylene oxide and subsequent hydrolysis (9, 11). However, the rising cost of propylene provides an incentive to find a substitute to propylene for this... 

The best materials are produced by curing unsaturated polyester during copolymerization with different types of unsaturated monomers and oligomers, such as styrene and its derivatives, methyl methacrylate, vinylacetate, sulfone-type compounds, allyl esters, and oligo(ester acrylates).5... 

CTBN and derivatives are also used in unsaturated polyester and vinylester resins but with less success. Studies have shown that the elastomer additive alone is very often immiscible in a polyester resin. 

It can be assumed that two separate networks with no covalent bonds between the UPR and the cyanate-based triazine network are formed. The possible addition of terminal hydroxyls from the unsaturated polyester to the —C = N bonds in BPA/DC is rather improbable as the addition of alcohols to cyanates, leading to iminocarbonate derivatives (Scheme 8), only occurs in the presence of strong alkali catalysts [134], The cyanate cyclotrimerization has been evidenced from disappearance of the 2230 and 2270 cm-1 and the appearance of 1370 and 1560 cm-1 absorption bands in the infrared spectra of the crosslinked IPN. 

The major use of phthalic anhydride is for ester derivatives used as plasticizers in the manufacture of flexible poly(vinyl chloride), e.g., wallpaper. The largest volume plasticizer is the di(2-ethylhexyl)phthalate. Other uses of phthalic anhydride are for unsaturated polyester and alkyd resins, for dye intermediates, and for isatoic anhydride (for the production of saccharin). 

Unsaturated polyesters (UPs) crosslinked with styrene are often used as a matrix of fiber reinforced plastics. Several reports treated the degradation of the crosslinked UPs with high temperature treatment in water (1,2), acetic acid (5), alcohols including glycols (4,5), and amines (6), often in the presence of catalysts. In these literatures, recovery of polymeric materials from the crosslinked UPs was not a main objective. However, in case we can hydrolyze polyester chains selectively, linear polystyrene derivatives can be obtained as recycled materials. 

Thermoset plastics have also been pyrolysed with a view to obtain chemicals for recycling into the petrochemical industry. Pyrolysis of a polyester/styrene copolymer resin composite produced a wax which consisted of 96 wt% of phthalic anhydride and an oil composed of 26 wt% styrene. The phthalic anhydride is used as a modifying agent in polyester resin manufacture and can also be used as a cross-linking agent for epoxy resins. Phthalic anhydride is a characteristic early degradation product of unsaturated thermoset polyesters derived from orf/io-phthalic acid [56, 57]. Kaminsky et al. [9] investigated the pyrolysis of polyester at 768°C in a fiuidized-bed reactor and reported 18.1 wt% conversion to benzene. 

The efficiencies of benzoin derivatives in promoting the light induced hardening of styrene-containing unsaturated polyester resins have been found to vary considerably (7), benzoin alkyl ethers and a-alkylated benzoins being more reactive than benzoin itself. However, as photoinitiators for the polymerization of bulk methyl methacrylate, benzoin and benzoin methyl ether exhibit comparable efficiencies (20), and this is also indicated for polymerisation of methyl acrylate in tert-butanol (21). The relative photoinitiating efficiencies of benzoin derivatives may be influenced by several factors, some of which will depend on the nature of the monomer system and the environment in which the polymerizations are carried out. 

Bisphenol A is used as a raw material to make polycarbonate and epoxy adhesives and can coatings. It is also used in flame-retardants, in unsaturated polyesters and in polyacrylate resins. Many foodstuff containers are made of these resins, including containers for oven and microwave cooking. Recent studies have shown that bisphenol type compounds have both mutagenic and cytotoxic properties [84]. Nerin et al. developed a fast screening method based on SPME and HPLC with fluorescence detection suitable for the analysis of several bisphenol derivatives and their degradation products in aqueous canned foods such as tuna, olives and corn [85]. The best results were obtained with carbowax and PDMS/DVB fibers. The detection limits were between 0.7 and 2.4ngmL while RSDs were between 14 and 32%. After the extraction parameters were optimized, the method was applied to... 

Polyesters derived from maleic anhydride and 2,2-di(4-hydroxyphenyl)pro-pane were copolymerised with styrene and then studied by CP/MAS NMR [39] spectroscopy. The three dimensional-crosslinked network formed by the polymerisation was examined using spin-lattice relaxation times in the rotating frame. A correlation between reaction conditions and the structure of the resulting material was found. The degree of residual unsaturation was determined by subtraction of two relaxation times from a linear additivity model used for erosslinked polymer systems. 

H5V and 2H5P have also been used as monomers for incorporation into polymerizing mixtures of unsaturated polyesters and styrene. Experiments were carried out with oligomeric polyesters made from maleic anhydride, phthalic anhydride, 1,3-dihydroxypropane (TO wt. ) and styrene (30 wt. ) ( 5.). Under the normal reaction conditions (benzoyl peroxide as the initiator), the two polymerizable benzotri-azole derivatives were essentially quantitatively incorporated when the feed ratio was between 0.5 and 5 mol. ... 

FR. Pead Sea Bromine] Bromine derivs. or ncmhalogenic prods. flame retardant for use in laminates, unsaturated polyesters, synthetic fibers, flexible yurethane foams, plastics, rubber, textiles, adhesives, and coatings. 

Tetrabromophthalic anhydride. Flame retardant in production of unsaturated polyester resins and rigid PU polyols co-hardener for epoxy resins cost efficient additive for latex emulsions derivatives used as flame retardants in diverse applications (wire coating, and wool, etc.). Crystals mp = 279-281 insoluble in H2O. Ethyl Corp. Great Lakes Firm Chem. 

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