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Crystalline and amorphous polymers have been obtained from the polymerization of phenyl glycidyl ether in the presence of tertiary amines. The crystalline fraction is high melting and insoluble at room temperature. The amorphous fractions are soluble at room temperature and their molecular weights are found to be ∼950 in benzene at 30°C. The yields of the crystalline fraction and the amorphous paste fraction decreased considerably with increasing the catalyst concentration and reaction temperature above 50°C. The yield of the liquid fraction, however, increased with increasing concentration of the catalyst and the reaction temperature. The x-ray diffraction analysis of the crystalline fraction shows that the fraction has 47–50% crystallinity and that its diffraction pattern is similar to that of poly(phenyl glycidyl ether) obtained by Noshay and Price. The infrared spectra of these fractions have been obtained in the region of 650–4000 cm.−1. These data are compared with those of polystyrene and poly(styrene oxide) and are used to make an assignment of the normal modes of the poly(phenyl glycidyl ether) molecule. On the basis of analyses of polystyrene and poly(styrene oxide), and a study of the combination bands, it has been possible to make a fairly satisfactory assignment of all of the benzene ring fundamentals of the CH2, CH, and skeletal modes.

The rates of reaction between benzoic acid and phenyl glycidyl ether in the presence of pyridine in toluene, nitrobenzene, various ethers, and mixed solvents as reaction solvents, are measured kinetically, and the following results obtained: (1) The rates are proportional to the concentrations of benzoic acid, phenyl glycidyl ether, and pyridine. (2) Plots of log A vs. the concentration of benzoic acid give a linear relation in toluene-nitrobenzene, but not in nitrobenzene-dioxane. (3) The energies and entropies of the activation increase as dioxane increases in the mixed solvents, toluene-dioxane and nitrobenzene-dioxane. (4) This reaction follows the isokinetic relationship in the mixed solvents. (5) The plots of the rate constants, k3 vs. the pKb of the ethers indicate a straight-line relation. (6) Both the complex ion and the free ion participate in the reaction; the contribution of the free ion to this reaction is proportional to the dielectric constants of the solvents.

Phenyl glycidyl ether, a model compound for bisphenol-A type epoxy resins, was reacted with alcohols in dioxane in the presence of boron trifluoride etherate. For isobutyl, sec-butyl, and n-butyl alcohols the reaction paths were similar and found to be: (1) epoxide–alcohol 1:1 addition, (2) epoxide–alcohol–dioxane addition, and (3) homopolymerization of the expoxide. With excess alcohol, homopolymerization could be minimized. In all cases, the predominant 1:1 adduct was shown to be 1-butoxy-3-phenoxy-2-propanol. There was indication that a small amount of the 1:1 adduct containing primary hydroxyl group was formed also. With tert-butyl alcohol, 3-phenoxy-1,2-propanediol was obtained as well. With phenol, the main reaction was homopolymerization of phenyl glycidyl ether.

Phenyl glycidyl ether was found to react with potassium starch alkoxide in dimethyl sulfoxide (DMSO) to give graft polymers in almost quantitative yields, both the monomer and the starch being incorporated completely into the graft polymer. No transfer reactions to monomer or solvent leading to homopolymerization was found. For this reason this system was used as a model for the study of the rate of the graft polymerization of alkylene oxides on starch and other carbohydrates. Comparison of the rates of the graft polymerization of phenyl glycidyl ether on starch alkoxide with that of the homopolymerization by potassium naphthalene in DMSO under comparable conditions showed that the former reaction was much slower. Rates of the graft polymerizations on dextrin and sucrose under comparable conditions, were similar to those obtained with starch. On the other hand, the rates of polymerization on poly(ethylene oxide) alkoxides of different molecular weights were similar to those obtained in the corresponding homopolymerization by potassium naphthalene, showing that neither the molecular weight of the initiator nor the viscosity of the reaction medium were the governing factors. This suggested that the lower rates obtained by using the carbohydrate alkoxides as initiators were connected with the heterogeneity of these reaction systems, the polymeric alkoxide being insoluble in DMSO. The systematic study carried out on the homopolymerization by potassium naphthalene in DMSO showed that the effective initiator was dimsyl anion obtained by interaction of potassium naphthalene with DMSO. The reaction was bimolecular, being first order to monomer and to initiator. The molecular weights increased with increasing monomer concentration and decreasing catalyst concentration, in accordance with a “living” polymerization system.

The kinetics of the reaction of phenyl glycidyl ether with aniline have been studied. The main kinetic and thermodynamic constants of the reactions involved have been determined.

Since the publication of Lidarzhik's paper [1] it has been thought that polymerization of epoxide compounds under the influence of tertiary amines can occur only in the presence of proton donating compounds. The polymerization of epoxide compounds that sometimes occurs with tertiary amines alone, without addition of proton donors, is explained by the effect of atmospheric moisture or the presence in the reaction mixture of hydroxylic impurities (in the hardening of epoxide resins for example). The present paper describes a study of the possibility of polymerization of epoxide compounds by tertiary amines in the absence of proton donating compounds, taking the polymerization of phenyl glycidyl ether (PGE) in the presence of dimethylhexylamine (DMHA) as an example.

Phenyl glycidyl ether has been polymerized, using aluminum catalysts, to crystalline as well as amorphous polymers. The crystalline fraction is high melting (ca. 200°) and insoluble at room temperature. The amorphous fractions are soluble at room temperature and some show rubber-like properties. The best yields of polymer were obtained when reactions were carried out in bulk, in open, stirred systems using aluminum isopropoxide and zinc chloride as cocatalysts.

The reaction of phenyl glycidyl ether (PGE) with benzoic acid (BA) catalyzed by tertiary amines and quarternary ammonium salts has been studied. The reaction catalyzed by quarternary ammonium salts is in goed agreement with second-order kinetics, according to-d[PGE]/dt=-d[BA]/dt=k, [PGE], [Cat. ]The tertiary amine catalyzed reaction, especially at the beginning ef the reaction, proceeds at a slewer rate than the reaction in the presence of quaternary ammonium salts. ln the reaction of PGE with BA in the prescnce of tertiary amines, catalyst amines react with PGE to form quarternary ammonium carboxylate salts, which is the actual catalyst in this reaction. The strtcture of the alkyl groups of amines has a large influence on the catalytic activity. ln the case of quarternary ammonium catalyst, the structure of alkyl groups does no affect the catalytic activity, but the type ef aniori associated with quarternary salt is very important.

A differential thermal analysis apparatus was constructed for the measurement of heats of polymerization. It featured an active cell in which the reacting mixture was contained in expendable thin-walled, narrow, cylindrical brass, or aluminum cartridges. The cartridges were tightly pressed into holes drilled into the body of the active cell and they, along with the solid reaction product, could be ejected therefrom at the completion of the reaction. A calibration cell was provided with small electric heaters which allowed known amounts of heat to be supplied to the apparatus in calibration runs. With this apparatus the mean value for three determinations of the heat of polymerization of epoxy resins, ca. 22 to 26 kcal./mole, could be measured to within a standard error of 0.37 kcal./mole (i.e., confidence limits of ±0.75 kcal./mole at the 95% confidence level). The heats of polymerization of phenyl glycidyl ether and of an epoxy resin were measured with ten and nine different curing agents, respectively. Primary amine curing agents released about 26 kcal./mole of epoxide reacted, tertiary amines, and boron trifluoride-ether complex each released about 22 kcal./mole. Mixed-type curing agents, which could react in part as tertiary amines, or boron trifluoride, and in part as primary amines could liberate intermediate amounts of heat.

The conductance of pyridinium benzoate has been measured in various solvents such as nitrobenzene, benzonitrile, o-dichlorobenzene, monochlorobenzene, and toluene, and its dissociation constant, K, was determined, using the Kraus and Bray's equation with the Λ0 value estimated from Walden and Ulich's rule and Stokes's law. The logarithm of K was found to be linear with the reciprocal of the dielectric constant, ε, or with the Kirkwood–Laidler–Eyring function, (ε − 1)/(2ε + 1). Kinetic studies for pyridine-catalyzed reaction between phenyl glycidyl ether and benzoic acid were also made in these solvents. Both the free ions and ion-pairs including the molecular addition complex participate in the reaction. The apparent rate constants, k″, of the reaction were shown to be linear with 1(K/c)1/2, c being the concentration of pyridinium benzoate. The intercepts of such lines give the rate constant for formation of ion-pairs, ki and the slopes yield the rate constant for formation of free ion, kf. The free ion rate constant increases fairly rapidly as the dielectric constant decreases, while the ion-pair reaction constant drifts downward comparatively slowly. A plot of the logarithm of kf or kf(K/c)1/2 against 1/ε or (ε − 1)/(2ε + 1) is found to be linear, but the plots of log ki against the same function are curved. The tangent of the curve is steeper for polar solvents than for non-polar solvents. The results have been compared with those predicted from classical dielectric theory.

N-Acylethylurethans reacted with phenyl glycidyl ether to produce 3-acyl-5-phenoxymethyl-2-oxazolidones, 5-phenoxymethyl-2-oxazolidone and N-(2-acyloxy-3-phenoxypropyl)ethylurethans. The reaction mechanism involving acyl migration was discussed.

The effect of the dielectric character of a solvent on the pyridine-catalyzed reaction between phenyl glycidyl ether and benzoic acid was studied in various pure and mixed aromatic hydrocarbons such as toluene, monochlorobenzene, o-dichlorobenzene, nitrotoluene, nitrobenzene, and toluene-nitrobenzene mixtures at temperatures ranging from 80 to 180°, and is discussed in terms of the modified Kirkwood's expression. The hydrogen-bonding effect of the solvent was also investigated for this reaction in toluene-dioxan and nitrobenzene-dioxan mixtures at temperatures ranging from 80 to 100° and in various ethers such as tetrahydrofuran, anisole and di-n-butyl ether at 65°0°. A linear relationship was found between the logarithm of the third order rate constants and pKa values of solvents, and can be described by the proposed rate equation. These show that in aromatic hydrocarbons the nonspecific electrical interactions are predominant, while the hydrogen-bonding character of the solvent can explain reasonably the rate data in solvents containing ethers, and should also suggest that the activated complex or the transition state species proposed plays an important role for this reaction in these solvents.

非プロトン溶媒-低級アルコール系混合溶媒中,核置換Nメチルアニリンとフェニルグリシジルエーテルとの開環付加反応の速度論的研究を行なった。この反応系ではフェニルグリシジルエーテルに対するN-メチルアニリンの付加(kA)と溶媒であるアルコールの付加(kB)が並行的に起こること,少量の非プロトン溶媒の添加により反応速度は著しく低下すること,60℃の反応のkAは添加溶媒の塩基性が大きいほど減少するが,kBはほぼ一定であることが認められた。さらに水素結合能力の小さい低級アルコールを用いると,kAは著しく減少するが,kBは比較的影響されない。数種の非プロトン溶媒-ブタノール系混合溶媒中のkAおよびkBに関するアレニウスプロットはいずれも上に凸である。各溶媒系にて置換Nメチルアニリンの反応のハメットρ値は-1.0～1.2であり,アルコールの反応では-2.2～-2.6である。これらの結果はN-メチルアニリン類の塩基性あるいは求核性が小さいため,N-メチルアニリンの付加反応ではエポキシドに対するアルコールの水素結合の寄与が相対的に重要であることを示唆するものであろう。ニトロベンゼンは特異な現象を示し,溶媒系に少量添加すると,kAが増大し,逆にkBが著しく減少する。またkAのρ値も-2.2となる。

キシレンおよびニトロベンゼン中,トリ-n-ブチルアミンを触媒(C)とし,80～130℃でフェニルグリシジルエーテル(E)とフェノール(P)の反応の速度,および反応次数は反応条件により変化し,キシレン中の反応は2次式-dE/dt=kcCPEで示されるが,kc値はCの濃度の影響を受けず,PE濃度により変化するのに対し,ニトロベンゼン中ではCが十分小のときは1次式-dE/dt=k3CEに従うが,Cが大きくなるとk3は減少し,P,E濃度の影響はない。また,キシレン:ニトロベンゼン混合溶媒中の反応は,キシレン95mol%以上では,2次式に従い,80mol%以下では1次式に従う。しかし,反応温度により反応次数は変化せず,またキシレン中の見掛けの速度定数kcの対数と反応温度の逆数は直線関係とならない。一方,イオン反応機構およびP,E,C各1分子よりなる錯化合物機構が競争的に起ると仮定して,理論的全速度式を求め,上記の実験結果を比較し,キシレン95～100mol%の溶媒中では錯化合物機構が支配的であり,ニトロベンゼン80～100mol%中ではイオン機構が優勢であると推定された

種々の溶媒中,トリ-n-ブチルアミンおよびナトリウムフェノキシドを触媒(B)として,フェニルグリシジルエーテル(E)と置換フェノール(P)の反応速度次数およびハメット則の反応定数ρ を求め,これより,エポキシドの塩基触媒開環反応の機構を考察した。トリ-n-ブチルアミンを触媒とするキシレン等非極性溶媒中の反応は-dE/dt=kcBPEなる3次式に従い-0.2

The anionic polymerization of 2,3-epoxypropyl phenyl ether initiated by sodium methoxide and dimsyl sodium in dioxane and in dimethyl sulfoxide has been studied. Kinetic and dielectric constant measurements have been recorded, and a mechanism for the initiation reaction with dimsyl sodium has been put forward. Polymerization initiated with dimsyl sodium revealed almost total absence of sulfur in the polymer by endgroup analysis. The reaction was shown to be inhibited by oxygen. Molecular weight determinations have indicated a reaction involving transfer to give polymers of lower than calculated Mn and a ratio of kp/ktr ratio of approximately 73. Gel-permeation chromatography suggests a narrow molecular weight distribution in the polymers prepared.

Isocyanates have been in use for some time as cross-linking agents for polyester and polyether polymers. These form three-dimensional network polymers on crosslinking and are familiar commercial materials. This cross-linking system has the merit that it is possible to produce a wide range of materials from a given isocyanate or polyester by varying the reaction proportions, catalysts and so on. In addition, these materials possess a useful range of physical properties. In the present work the chemical basis of cross-linking epoxide resins with isocyanates has been investigated. Previous work on the subject has been largely empirical and though certain workers have produced cross-linked polymers by this means, the precise nature of the cross-linking process has not been established. As an initial step it was decided to investigate the nature of the link between the two types of compound, using monofunctional model compounds. These were phenyl glycidyl ether (2-3 epoxy propyl phenyl ether), and phenyl isocyanate. Phenyl glycidyl ether resembles in structure the active part of the epoxide resin molecule, and phenyl isocyanate is similar to toluene di-isocyanate, which is frequently used in isocyanate cross-linking mechanisms. A reaction has been found to take place giving a crystalline material which is a one-to-one addition compound of the two reagents, together with a red oil, which may be a mixture of alkyl anilides. The structure of the crystalline material has not been fully proved, but is believed to be a 2-oxazolidone.