content_image/931003.jpg content_image/931002.jpg content_image/931001.jpg
[0051] When the phenol monomer is used as both the acid catalyst and as the phenol monomer, the reaction to form the condensate may be considered self-catalyzing, and under such circumstances a separate acid and/or base catalyst is not needed. 

[0052] Optionally, additional compounds may be used with the reaction mixture and/or the epoxy resin. One additional compound is a stabilizer that may be a non-reactive diluent that can reduce the viscosity of the condensate or resin. The stabilizer may be an organic compound, and may be cyclical, acyclical, aliphatic, or aromatic in form. Suitable stabilizers may include, and are not limited to, the following classes of compounds: esters, hydroxyaryl moieties, dihydroxyaryl moieties, amides, alcohols, ketones, and combinations and subsets thereof. Examples of suitable stabilizer groups include alkylphenols, glycols, glycol ethers, and combina› tions and subsets thereof. Examples of stabilizers include compounds selected from the group of cresol, N-methyl pyr› rolidone, phenol, hydroquinone, triethylcitrate, butyrolac› tone, glycerol, ethylene glycol, and combinations thereof. The stabilizer may be added to the reaction mixture from 0.1 wt. % to 2 wt. % of the reaction mixture, such as the triazine› phenol-aldehyde condensate. The stabilizer is preferably added when a solid of the condensate is to be formed and maintained. If a liquid solution of the condensate is to be performed, preferably a solvent is added to the condensate. 

[0053] Optionally, a base catalyst may be introduced with the acid catalyst described herein. The quantity of base cata› lyst, also referred to as a catalytically effective quantity of amine catalyst, will typically vary from about 0.01 % to about 1 % based on the weight of the arylhydroxy monomer charged and preferably from about 0.08% to about 0.3%, for example, from about 0.1 % to about 0.2%. The base catalyst may have a pK basicity, or pKb from about 7 to about 11.5. 

[0054] The base catalyst may be an aliphatic, a cycloaliphatic, and/or a heterocyclic amine having a pK basicity (pKb) of 10 or more, and may further be a secondary or tertiary amine. A tertiary amine may have the formula R$_{3}$N, with each R may be an alkyl functional group having one to seven carbon atoms, and the nitrogen atom may be part of a heterocyclic ring. In this regard, each of the alkyl groups may be the same or different. A secondary amine having a pKb of 10 or more may have the formula R$_{1 }$R$_{2}$NH, with each R may be an alkyl functional group of2 to 4 carbon atoms. Examples of amines for use as the base catalyst include triethylamine, tributylamine, N-ethyl piperidine, 2-di(n-butylamino )etha› nol, 2-di(isopropylamino) ethanol, N-methylpyrrolidine, N,N-dimethyl cyclohexylamine, diethylamine, di-n-buty› lamine, diisopropylamine, piperidine, pyrrolidine, and com› bination thereof. 

[0055] Examples of amines having a pK basicity of less than 10 include, and are not limited to, N-methylmorpholine, N-methyl diethanolamine, triethanolamine, N,N’-dimeth› ylpiperazine, 4-methylpyridine, 2,4-dimethylpyridine, N,N› diethylaniline, and N,N-dimethylbenzylamine, and combina› tions thereof, may be used as the base catalyst. 

## The Triazine-Arylhydroxy-Aldehyde Condensate 

[0056] In one embodiment, the triazine-arylhydroxy-alde› hyde condensate may be represented by the following for› mula: 

[0057] The R$_{7 }$and Rs functional groups of the formula (III) may each independently be a hydrogen atom or a functional group having formula (IV): 

<img src='content_image/931003.jpg'>

where n may be an integer of O to 20 and X is an integer of 1 or 2. The Rs and R$_{6 }$ functional groups may be independently a hydrogen atom or a functional group selected from the group of an alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms with at least one carbon atom being substituted with a hydroxybenzene group, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, a hydroxybenzene, and combinations and subsets thereof. The Rs and R$_{6 }$ functional groups may jointly form a common aromatic ring with or without a hydroxyl group. 

[0058] The R$_{7 }$ and Rs functional groups may also jointly form a benzoxazine functional group represented by the for› mula: 

[0059] In Formula (V), the Rs and R$_{6 }$functional groups are described above with regard to formula (IV), and Y is an integer of O or 1. The benzoxazine functional group may be formed during the high pKa process as described herein when the triazine monomer and aldehyde monomer comprise an aldehyde modified triazine monomer such as HMMM. Also, the benzoxazine functional group may be formed when the para position of the phenol monomer is not available for reacting with the aldehyde as in a para substituted phenol monomer such as para-cresol. If the Rs functional group is not part of formula (V), the Rs functional group may be a hydro› gen atom or a functional group having the formula (IV). 

[0060] If the R$_{7 }$ and Rs functional groups of the formula (III) are both hydrogen atoms, then between the R$_{9 }$ and R$_{10 }$ functional groups of the formula (III), at least one of the R$_{9 }$ and R$_{10 }$functional groups may be a functional group having the formula (V) or may be a functional group selected from 

<img src='content_image/931002.jpg'>

<img src='content_image/931001.jpg'>

(III) 

(IV) 

(V) 

