Synthesis resin

With the improvement of refining and purification techniques, many pure olefinic monomers are available for polymerization. Under Lewis acid polymerization, such as with boron trifluoride, very light colored resins are routinely produced. These resins are based on monomers such as styrene, a-methylstryene, and vinyltoluene (mixed meta- and i ra-methylstyrene). More recently, purified i ra-methylstyrene has become commercially available and is used in resin synthesis. Low molecular weight thermoplastic resins produced from pure styrene have been available since the mid-1940s resins obtained from substituted styrenes are more recent. 

Coumarone—indene or coal-tar resins, as the name denotes, are by-products of the coal carbonization process (coking). Although named after two particular components of these resins, coumarone (1) and indene (2), these resins are actually produced by the cationic polymerization of predominantly aromatic feedstreams. These feedstreams are typically composed of compounds such as indene, styrene, and their alkylated analogues. In actuaUty, there is very tittle coumarone in this type of feedstock. The fractions used for resin synthesis typically boil in the range of 150—250°C and are characterized by gas chromatography. 

G-5 Aliphatic Petroleum Resins. Carbocationic polymerization of C-5 feedstreams has been accomptished with various Friedel-Crafts catalyst systems. Table 3 compares the efficiencies of selected Lewis acids ia the polymerization of a typical C-5 stream containing 43 wt % C-5—C-6 diolefias and 47 wt % C-5—C-6 olefins (20). Based on weight percent yield of resia at equimolar coaceatratioas of catalyst (5.62 mmol/100 g), efficieacy follows AICI3 AlBr3 > BF3etherate-H20 > TiCfy > SnCl. The most commonly used catalyst in petroleum resin synthesis is AlCl. ... 

G-9 Aromatic Petroleum Resins. Feedstocks typically used for aromatic petroleum resin synthesis boil in the approximate range of 100—300°C at atmospheric pressure, with most boiling in the 130—200°C range. The C-9 designation actually includes styrene (C-8) through C-10 hydrocarbons (eg, methylindene). Many of the polymerizable monomers identified in Table 1 for coumarone—indene type cmdes from coal tar are also present in aromatic fractions from cracked petroleum distillates. Therefore, the technology developed for the polymerization of coal-tar cmdes is also appHcable to petroleum-derived aromatic feedstocks. In addition to availabiHty, aromatic petroleum resins offer several advantages over coumarone—indene resins. These include improved color and odor, as weU as uv and thermal stabiHty (46). 

As we have already mentioned, the cure of resoles takes place primarily through further extension of the condensation process, though the conditions are usually considerably different from those of synthesis. The changes in conditions normally include exposure to much higher temperatures and higher concentrations of polymer than are seen in resin synthesis. The pH of the medium may also... 

Ion exchange resin synthesis paths for the preparation of ionic liquids (adapted from... 

Alkyd resin synthesis. This synthesis consists of two steps. In the first step, a triglyceride oil is reacted at ca. 250°C with polyols, such as glycerol or pentaery-thritol, in tire presence of a basic catalyst to form a monoglyceride. In the second step, phthalic anhydride, with or without another dibasic acid such as maleic anhydride, is added to the reaction medium and reacted at high temperature. The resulting product is a branched polyester (Scheme 2.56). 

The acidic catalysts used for these reactions include formic acid, HX (X = F, Cl, Br), oxalic acid, phosphoric acid, sulfuric acid, sulfamic acid, and p-toluenesulfonic acid.4 Oxalic acid is preferred since resins with low color can be obtained. Oxalic acid also decomposes at high temperatures (>180°C) to C02, CO, and water, which facilitates the removal of this catalyst thermally. Typically, 1-6 wt % catalyst is used. Hydrochloric acid results in corrosive materials and reportedly releases carcinogenic chloromethyl ether by-products during resin synthesis.2... 

A Statistical study of phenol-formaldehyde resol resin synthesis reaction... 

Figure 7 illustrates the use of HPGPC to aid a resin chemist in developing an in-house isocyanate crosslinker for a powder coating system. Isocyanate crosslinker X-02 gave desired properties and is considered the standard. At the early stage of the development, resin X-03 was initially made. By changing the types of reactants, molar ratio of reactants and reaction conditions, resin X-36 was the next iteration in the resin synthesis process. Finally, X-36 was fine-tuned to produce X-38 which matched X-02 in both its chemical reaction properties and its MWD. 

The use of the phenyl phosphate group as both a solid support attachment site and a crucial binding element represents what has been referred to as a pharmacophore-linking strategy [26]. We explored a variety of phenyl phosphate tether functionalities to provide resins varying in substitution pattern and in chemical flexibility (Scheme 1 and Table 4) [22]. All phenyl phosphate resins were synthesized in batch quantities of 20 g or more. Resin synthesis began with the addition of either /mnethoxy-benzyl alcohol or benzyl alcohol to commercially available bis(diisopro-pylamino)chlorophosphine, followed by addition of the diversity phenol [(Ri)-OFl, DIAT (diisopropylamino tetrazole)]. Displacement of the... 

Triisopropylbenzenesulfonyl)-3-nitro-1,2,4-triazole in the presence of 4-rtiorpholine pyridine-1-oxide was used with advantage as a coupling reagent for a solid-phase (p-alkoxybenzyl ester type resin) synthesis of peptides such as Leu-AIa-Gly-Val-OH or Leu-enkephalinamide (Tyr-Gly-Gly-Phe-Leu-NHs). The overall yield in the latter case was 70%, the purity of the peptide was 85-90%, and racemization was virtually zero.[38]... 

The difference between the pH profiles of the two stages of urea-formaldehyde resin synthesis is taken advantage of in the production of these resins (Figure 19.2). In general, the commercial production of urea-formaldehyde adhesive resins is carried out in two major steps. The first step consists of the formation of methylolureas under basic conditions (pH 8 to 9), to allow the methylo-lation reactions to proceed in the absence of reactions involving the condensation of the methylolureas. 

Fig. 9. Suitable cyclic carboxylic anhydrides for hyperbranched resin synthesis...

Typically lightly cross-linked gel-type resins are prepared in the absence of any solvent or porogen. However it is possible to include relatively large volumes of thermodynamically compatible solvent in the polymerization without inducing any phase separation at the low levels of cross-linker used in gel-type resin synthesis. 

T2 resin synthesis of substituted amines [142], amides (peptides) [143], (thio)ureas [143,... 

Nucleophile substitution of the T1 resin synthesis of phenols, biaryls, alkyl arenes, azides, aromatic hydrazines, halides, ester, azo compounds cinnolines, benzotriazoles [129-137, 140, 141]... 

Protection Schemes for the On-Resin Synthesis of Cyclic Peptides... 

Resin synthesis of OSL-modified phenol-formaldehyde resins. 

Appreciation is expressed to the following MFPUL employees Dr. A. L. Wooten (retired) for resin synthesis Gary Stovall and George Miller for resin and flake board sample preparation and testing and Lynn Prewitt for GFC work. Materials were donated in support of this project by Borden... 

The main reactions involved in alkyd resin synthesis aie poly condensation by esterification and ester interchange. Figure 1 uses the following symbols to represent the basic components of an alkyd resin. 

On-Resin Synthesis of a Cyclic Peptide Library Using Lys and Glu Side-Chains... 

The divide-couple-recombine (DCR) method,9 also known as split-resin synthesis,8 involves the coupling of reactants to individual aliquots of resin followed by thorough mixing of the resin portions. The resin is then... 

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