Alkyl resins

Modified melamine resins are also employed commercially. Alkylated resins analogous to the alkylated urea-formaldehyde resins provide superior coatings but are more expensive than the urea-based products. 

Benzoic acid CgHjCOjH Alkyl resins, chemical intermediate, oil drilling additive, medicines... 

Poly(vinyl chloride) 1838 1931 Thermoplastics (synthetic fiber) Alkyl resins 1847 1915 1926 1928 Thermosets (coatings)... 

Uses Preparation of sodium and butyl benzoates, benzoyl chloride, phenol, caprolactum, and esters for perfume and flavor industry plasticizers manufacture of alkyl resins preservative for food, fats, and fatty oils seasoning tobacco dentifrices standard in analytical chemistry antifungal agent synthetic resins and coatings pharmaceutical and cosmetic preparations plasticizer manufacturing (to modify resins such as polyvinyl chloride, polyvinyl acetate, phenol-formaldehyde). 

The Mitsunobu reaction is usually only suitable for the alkylation of negatively charged nucleophiles rather than for the alkylation of amines, and only a few examples of such reactions (mainly intramolecular N-alkylations or N-benzylations) have been reported (Entry 15, Table 10.2). Halides, however, are very efficiently alkylated under Mitsunobu conditions, and it has been found that the treatment of resin-bound ammonium iodides with benzylic alcohols, a phosphine, and an azodicarboxylate leads to clean benzylation of the amine (Entry 9, Table 10.3). Unfortunately, alkylations with aliphatic alcohols do not proceed under these conditions. The latter can, however, also be used to alkylate resin-bound aliphatic amines when (cyanomethyl)-phosphonium iodides [R3P-CH2CN+][r] are used as coupling reagents [62]. These reagents convert aliphatic alcohols into alkyl iodides, which then alkylate the amine (Entry 10, Table 10.3). 

Uses Xylene occurs in the manufacture of different petroleum products and as an impurity in benzene and toluene. It is a colorless and flammable liquid. Commercial xylene is a mixture of three isomers, namely, ortho-, meta-, and paraisomer. It is extensively used in industries associated with paints, rubber, inks, resins, adhesives, paper coating, solvents, and emulsifiers. It also is used in the manufacture of plasticizers, glass-reinforced polyesters, and alkyl resins. Xylene is used as an important raw material. 

There are numerous types of paint employed in the protection of steel and they are designed to meet the conditions imposed by the environment in which they are expected to function. For steel exposed to the atmosphere, the most common type of paint system is based on alkyl resin and this may be mixed with other types or may itself be chemically modified for a specific purpose, e.g. vinyl toluenated or styrenated to give rapid drying. Other generic types are chlorinated rubber, vinyl, acrylic, epoxy, and polyurethane. All have particular attributes and limitations and selection is usually a matter of discussion between user and supplier. 

Significant quantities for formaldehyde are consumed in the production of other resins or polymers such as polyacetyls, melamine resins, and alkyl resins. Formaldehyde is also used in rubber/latex manufacture, textile treatment other than permanent-press fabrics, dye manufacture and use, photoprocessing chemicals, laboratory fixatives, embalming fluids, disinfectants, and preservatives. Formaldehyde can also be emitted by combustion appliances, wood fires, tobacco smoke, and in indoor chemistry. 

Epoxy resin ester paint, Epoxy modified alkyl resin paint,... 

Alkylation Resin 41 (1 g, based on Wang resin, 1.11 mmol g ), lithium iodide (1 equiv.), and glycidyl tosylate (10 equiv.) were suspended in dry NMP (8 mL) and the mixture was stirred for 10 min at ambient temperature under an argon atmosphere. Lithium bis(trimethylsilyl)amide (1 m in THF, 2 equiv.) was then added dropwise and the reaction mixture was stirred overnight. Thereafter, the resin 42 was filtered off and washed with DMF (10 times), DMF/CH2CI2 (1 1, five times), and CH2CI2 (five times), and dried in vacuo. 

Figure 7.15. Gel-permeation chromatography (GPC) analysis of good and bad alkyl resins using UV detection. Reprint with permission from reference 28.

The first stage in the manufacture of alkyl resins may be represented by... 

Properties. Alkylated amino resins can be classified into two general classes (1) polymeric, partially alkylated resins which have a lower solids content and (2) the more monomeric, fully and partially alkylated products which have a higher solids content. 

Fully alkylated amino resins require strong acid catalysis for fast and/or low-temperature cross-linking. Their catalysis mechanism is different from that of partially alkylated resins which respond to weak acid catalysts or general acid catalysis. A fully alkylated melamine resin catalyzed by a strong acid catalyst is a faster curing (cross-linking) agent than a partially butylated amino resin. 

The catalysts which are predominately used are p-toluenesulfonic acid, dodecyl-benzenesulfonic acid, dinonylnaphthalenedisulfonic acid, and their amine salts [2.152]. Compared to partially alkylated amino resins, fully alkylated resins have a lower tendency to undergo self-condensation and produce films which are hard and still more flexible. 

Fully alkylated MF resins may contain <0.25% free formaldehyde. Partially alkylated resins usually have a higher content (< 3%). The free formaldehyde content of an amino resin is largely responsible for the formaldehyde released during the application process. This is only a small fraction of the total formaldehyde released. Hydrolysis of the amino resin and subsequent dehydroxymethylation during curing account for > 80% of the total formaldehyde release (see also p. 84). 

Although resins with a high amino content have a higher content of free formaldehyde than fully alkylated resins, they release lower amounts of formaldehyde during cure. The lowest amount of formaldehyde during application and cure is released by alkylated glycoluril-formaldehyde resins [2.155]. 

Condensation polymers nylon, teflon, polymethane, polycarbonate, amino resins, alkyl resins, and silicone resins... 

Cellulose acetate-propionate is used in flexographic ink formulations. The acetate-butyrate mixed esters are used in sheeting, molded plastics, hot melt dip coatings, lacquer coating and film products. The mixed proprionate-butyrate ester has excellent compatibility with oil-modified alkyl resins and is used in wood furniture coatings. 

Alkyl resins (mineral and glass fibre) Switches, relays bases and capacitor encapsulation... 

Alkyl resins Short glass fiber Automotive, ignition, switches, relay bases... 

Phthalic anhydride in alkyl resins was first saponified, precipitated as potassium phthalate, the alcoholate was dissolved in sulphuric acid and the curve was recorded in the presence of tetramethylammonium bromide. < > However, the application of the two-phase saponification, mentioned in the previous paragraph, seems to be more convenient. 

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