Amine functional acrylics

Amine functional acrylates, polymeric amines and copolymerizable tertiary amines which accelerate the cure of UV system have also been proposed (see, for example, (10.46) and Ref. [124] studied in Ref. [125]). 

Electro deposition systems (which are considered later) are the only main exception to acid functional acrylic resins, where cathodic deposition which is increasingly favoured requires amine functional acrylics. 

Acid functional acrylics neutralised with tertiary amines are used for anodic systems, whilst amine functional acrylics neutrahsed with acid are used for cathodic systems. As a general rule cathodic systems are preferred due to less metal ions leaving the metal, but cathodic systems are normally more expensive. 

Substrate adhesion depends upon monomer composition. Hydroxy and carboxyl acrylics are better than most. Amine functional acrylics also exhibit, good adhesion. Acrylics have a characteristic odour, which may be classed as strong by some people. This is due to unreacted monomer. The cured films are generally taint free and certain acrylic resins are approved for direct food contact. They may impart an off flavour to beers. 

The carboxy/epoxy system displays a very fast lacquer type dry but, in comparison to a 2 pack polyurethane, relatively slow through cure. Tertiary amines can be used to enhance the cure of the coating. However, careful selection of the catalyst is critical since some amines can also make the coating water sensitive. There is also the potential to catalyse the system internally by incorporating an amine functional monomer onto the backbone of the acrylic resin by copolymeiisation of amine functional acrylic or vinyl monomers. 

Another approach for the synthesis of networks relies on the polycondensation of multifunctionalized polyesters with the appropriate multifunctionalized agent, provided that one of the partner is at least tri-functionalized. Toward this end, several reaction have been reported, such as the Michael addition of amines onto acrylates [184], the coupling of ketones and oxyamines [185], the click copper(II)-catalyzed azide-alkyne cycloaddition [186], and esterification reactions [25, 159, 187]. Interestingly, if esterification reactions are used, the crosslinks are then degradable. 

Other carboxylate-dye interactions have been reported. Ethylenediamine tetracarboxylic acid (EDTA) and its salts are well known reductants for a variety of dyes (54,55). The amino-acid N-phenylglycine can be photooxidized and induce polymer formation (26,56,57). Studies of the efficiency of photopolymerization of acrylate monomers by MB/N-phenylglycine combinations as a function of the pH of the medium suggest that either the amino group or the free carboxylate can act as an electron donor for the dye excited state, but that the amine functional-lity is the more efficient coinitiator (10). Davidson and coworkers (58) have shown that ketocarboxylic acids are photode-carboxylated by electron transfer quenching of dye triplet states under anaerobic conditions. Superoxide formation can occur when oxygen is present. 

The performance of the new water-borne silanes was studied. The water-borne silanes were comparable to conventional silanes in most cases. In several cases, notably with acrylic latices, the new silanes excelled. In particular, the data obtained suggest that the new amine functional materials may exhibit superior performance to conventional silanes in moist environments. 

The acrylic weak base resins are synthesized from copolymers similar to those used for the manufacture of weak acid cation-exchange resins. For example, under appropriate temperature and pressure conditions, a weak acid resin reacts with a polyfunctional amine, such as dimethylaminopropylamine [109-55-7] (7) to give a weak base resin with a tertiary amine functionality. 

Tomalia developed the polyamidoamine (PAMAM) dendrimers via the repetition of a simple two-step procedure (1)1,4-addition of a nucleophilic core (e.g. ammonia, ethylene diamine or tris(2-aminoethyl)amine) to methyl acrylate followed by amida-tion of the resulting ester with an amine functionality (e.g. ethylene diamine, propylene diamine) [188, 189] (see Fig. 18). PAMAM dendrimers could be synthesised as high as generation seven, due to the high yield of the synthetic procedure. From that point the steric considerations began to dominate, making the addition of any subsequent generations difficult [168]. 

Although dimeric Sharpless ligands as catalysts showed impressive results in related organocatalytic transformations, they provided only limited success in asymmetric MBH reactions (Scheme 5.12) [70]. These compounds are bifunctional catalysts in the presence of acid additives one of the two amine function of the dimers forms a salt and serves as an effective Bronsted acid, while another tertiary amine of the catalyst acts as a nucleophile. Whereas salts derived from (DHQD)2PYR, or (DHQD)2PHAL afforded trace amounts of products in the addition of methyl acrylate 8a and electron-deficient aromatic aldehydes such as 27, (DHQD)2AQN, 56, mediated the same transformation in ee up to 77%, albeit in low yield. It should be noted that, without acid, the reaction afforded the opposite enantiomer in a slow conversion. 

The most important monomers (> 95 % by weight) for silicone synthesis are the methyl chlorosilanes. Next to them are the phenyl chlorosilanes, methyl phenyl chlor-osilanes, methyltrifluoropropyl chlorosilanes, and a variety of silanes containing organic functional groups such as hydroxyl, amine, epoxy, acrylate and carboxyl which are responsible for the different products. 

It is well known that primary amines are efficient initiators for the polymerization of Leuch s anhydrides (oxazolidinediones) and that initiation proceeds by the addition of the amine to the monomer. This pathway has been utilized recently to synthesize polypeptide macromonomers bearing a terminal p-vinylbenzyl group 88). Copolymerization of these macromonomers with a vinylic or acrylic comonomer yields graft copolymers with polypeptide grafts. Alternately, the monomer adduct (IV) was copolymerized with styrene, and the primary amine functions of this polymer were used to initiate the polymerization of an oxazolidinedione whereby polypeptide grafts are formed 89). Such graft copolymers may be of interest for biomedical applications. 

Table 14.6 illustrates typical improvements noted in epoxy hybrid formulations with vinyl chloride, acrylic, and styrene butadiene lattices. Tensile strengths of cured, latex-saturated paper substrates are listed in absolute numbers while those of latex-epoxy hybrids are listed as percent increases in tensile strength over that of the latex alone. The mechanisms believed responsible for these improvements are (1) cocuring of the epoxy group with carboxyl and amine functional groups present on the latex backbone and/or (2) homopolymerization of the epoxy catalyzed by the tertiary amine included in some hybrid formulations. 

The first step in this minimalistic transcription/translation process that mimic genealogical criteria in Fig. 46 involves Michael addition of methyl acrylate to the nucleophilic ammonia surface to produce an electrophilic, carbomethoxy functionalized surface, followed by reaction with ethylenediamine to translate the functionalized dendrimer surface back to a nucleophilic primary amine functionalized surface. This iterative sequence is the key in providing alternating nucleophilic... 

Michael addition is a facile reaction between nucleophiles and activated olefins and alkynes in which the nucleophile adds across a carbon-carbon multiple bond [25], For the preparation of hydrogels, the hydroxyl, thiol or amine functionalities have been reacted with vinyl sulfones [26-28], acrylates [29-31], acrylamides [32], and maleimides [33, 34] (Scheme 2). 

In each case, a solution of the desired dlol in 2-hydroxyethyl acrylate was charged to the addition funnel and the isophorone diisocyanate, inhibitor and urethane catalyst were charged to the reaction flask with the water bath in place. The addition took one hour and after a two hour hold at room temperature, the appropriate trifunctional branching agent (TBA) was added. when the amine functional TBA was used, a 50 50 solution of the TBA in the... 

Initial experiments were undertaken with morpholine, dicyclohexylamine and dibutylamine terminated GPTA systems as well as the diethylamine sample which has already been investigated in previous work (14,15). The effect of Microscal irradiation on the increase in hydroxyl index of these amine acrylates is illustrated by the data in Table I. This shows that the nature of the terminal amine functionality has a marked effect on the hydroxyl index profile during irradiation. The following order of increasing hydroxyl index was observed relative to amine functionality ... 

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