Methyl Methacrylate (MMA) was grafted to cis-1, 4-polybutadiene (PB) by γ-irradiation in benzene solution. Graft polymer was separated by alternative extraction. Free polymethyl methacrylate (PMMA) was extracted with acetone, and unreacted PB was extracted with n-hexane. MMA content and number average molecular weight (M_n) of the graft polymer were determined. PMMA side chain in the graft polymer were separated from backbone chain by ozonolysis of the latter, and fractionated by fractional precipitation with benzene-methanol. M_n of each fraction was measured. This led to the calculation of the molecular weight distribution curve, and number and weight average molecular weights of side chain PMMA. The molecular weight distribution, M_n and M_w, of acetone extracted free PMMA were also obtained by the same method as for as side chain PMMA.
In the present paper, it was found that average number of side chain per backbone chain was nearly unity and molecular weight distribution of side chain was nearly same as that of free PMMA. A few weight percentage of acetone extract was also found to consist of graft polymer containing longer PMMA side chain.

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By differential scanning calorimeter, it is found that the thermal behaviour of polyethylene-terephthalate crystallized isothermally from the molten state is different by crystallization time. In the initial region of the secondary crystallization process the thermogram shows two or three endotherrnic peaks and in the region of long crystallization time shows one or two endothermic peaks.
1) Between crystallization time t and average lamellar thickness L_t and between t and melting temperature T_m (L_t), we obtained next equations independently of crystallization temperature T_c, _??_
where B and C are constants.
2) The relation between T_c and T_m (L*_t) is given by the next two equations, _??_
where t* is the time at which L_t=L*_o, L*_t is the lamellar thickness when distribution of lamellar thickness is maximum at the time t of the secondary crystallization process and T_m^o is the equilibrium melting temperature.
3) The (surface free energy)/(heat of fusion) =σ_e (L_t)/ΔH_f (L_t) decreases with increasing of t independently of T_c and for constant crystallization time decreases with increasing of T_e.

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The PVA fiber grafted with styrene were prepared by the emulsion method using potassium persulfate (KPS) as the catalyst.
The viscoelastic properties of these fibers were investigated as a function of degree of grafting. The results are as follows.
1) Viscoelasticities, glass transition temperatures and thermograms of differential thermal analysis showed that the two components (PVA and polystyrene) seem to exist in two seperated phases.
2) The modulus of the copolymer with high degree of grafting was represented by a simple parallel mechanical model, that is, the complex modulus E* of this system was described by the equation of E*=λE_PS+(1-λ)E_PVA*, where λ is the volume fraction of polystyrene, E_ps* and E_PVA* are the complex moduli of polystyrene and PVA fibers, respectively.
3) These graft copolymers behaved almost in the same way as the mechanically blended system which was composed of the corresponding two components.

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The main subject of this article is to elucidate the reason why some properties of poly-(vinyl alcohol)(PVA) derived from poly (vinyl acetate) depend on the polymerization temperature of vinyl acetate (VAc). Five different series of PVA samples were prepared, and their properties, such as swelling in water, blue color development in iodine solution and melting temperature were examined in relation to their tacticities and 1, 2-glycol contents. PVA samples from poly (vinyl acetate) were prepared by radical polymerization of vinyl acetate over a range of temperature from-78°C to 80°C. The PVA samples obtained from the poly (vinyl acetate) vary in 1, 2-glycol content from 0.6 to 2.2 mole % and the tacticity in s-diad from 57.0 to 54.6%. Two series of PVA samples with different tacticities and having no 1. 2-glycol were prepared by cationic polymerization of vinyl t-butyl ether and vinyl trimethylsylil ether in solutions of different polarities at-78°C. PVA samples with different 1, 2-glycol contents were obtained from VAc-divinyl carbonate copolymer and VAc-vinylene carbonate copolymer. Melting temperature and resistance to hot water increase with increasing s-diad tacticity of PVA, but the degree of swelling in water at 30°C and PVA-iodine blue color reaction are not sensitive to the variation of s-diad tacticity from 59 to 46%. The swelling degree at 30°C and PVA-iodine blue color reaction are almost uniquely dependent on the amount of 1, 2-glycol content in PVA chain, as far as the samples in this study are concerned. These findings seem to indicate that the increase in crystallinity of PVA arising from the decrease in the polymerization temperature of VAc is largely attributable to the decrease in 1, 2-glycol content.

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The polymerization of methyl methacrylate (MMA) was investigated using magnesium amide derivatives, which were obtained by the reaction of dialkyl magnesium with primary or secondary amines, as catalysts.
When the polymerization was carried out in toluene at-78°C, the stereoregularity of the polymer as well as the catalytic activity was extensively influenced by the nature of the amide group of the catalyst. When piperidine was used as an amine component, highly syndiotactic PMMA was obtained. On the other hand, isotactic PMMA was obtained with the catalyst using pyrrole as an amine.
The effect of reaction conditions on the polymerization by these catalysts was also studied.

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The homopolymerization and copolymerization 2, 4-diamino-6-vinyl-s-triazine (DAVT) were studied under various conditions. The homopolymerization of DAVT was carried out at 50-80°C by azobisisobutyronitrile (AIBN) in dimethylsulfoxide (DMSO) and the rate of polymerization at 60°C was expressed by the followinr eauation.
R_p=5.50×10^-3 [AIBN] ^0.6 [M] ^1.8
where [M] is monomer concentration.
The over-all activation energy was obtained to be 17.3kcal/mol.
The copolymerization parameters of DAVT (M₂) were determined from the copolymerizations with styrene (St)., methylmethacrylate (MMA) and vinyl acetate (VAc). The monomer reactivity ratios and the Q₂ and e₂ values for DAVT were as follows
for St-DAVT, r₁=1.30, r₂=0.65, Q₂=0.55, e₂=-0.38,
for MMA-DAVT, r₁=1.03, r₂=0.22, Q₂= 0.44, e₂=-0.81,
for VAc-DAVT, r₁=0.05, r₂=13, Q₂=0.60, e₂=-0.87

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A new monomer, 2-amino-4-o-toluidino-6-vinyl-s-triazine (ATVT), was synthesized from the reaction of o-tolylbiguanide with acrylyl chloride.
The homopolymerization of this monomer was carried out at 50-80°C in dioxane with azobisisobutyronitrile (AIBN) as an initiator and the rate of polymerization (R_p) at 60°C was represented by following equation.
R_p= 2.37×10^-3 [AIBN] ^0.5 [M] ^1.0
Where [M] is monomer concentration.
The over-all activation energy was obtained to be 16.6kcal/mol.
The copolymerizations of this monomer (M₂) with styrene (St), methylacrylate (MA), acrylonitrile (AN) or vinyl acetate (VAc) were also carried out at 60°C in dioxane. The monomer reactivity ratios (MRR) were determined as follows:
for St-ATVT, r₁=0.45, r₂=0.93,
MA-ATVT, r₁=0.33, r₂=1.22,
AN-ATVT, r₁=0.3, r₂=0.03,
VAc-ATVT, r₁=0.001, r₂=17
The Q and e values for ATVT were calculated as 1.05 and 0.13, 0.72 and -0.36 respectively from the MRR values for the copolymerizations with St and with MA.

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Photopolymerization of vinyl monomers including styrene, methyl methacrylate was carried out at 30°C in the presence of diphenyl disulfides substituted with either amino-or isocyanato-groups at p- and p'-positions. End group analysis of the polystyrene incorporated with isocyanato-groups was made, and together with M_n values measured from viscometry, it was found that the polystyrenes have functional groups at both ends.
Furthermore, polyaddition reactions on the polymers were attempted.

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The copolymerization of acrylonitrile (AN) with sodium methallyl sulfonate (SMAS) in dimethyl sulfoxide (DMSO) at pH 7, in aqueous DMSO solution (6% H₂0) at pH 7, in DMSO at pH 1.5, in aqueous solutions at pH 7 and at pH 1.5 has been investigated. Monomer reactivity ratios at 45°C for AN and SMAS were found to be r₁=0.45, r₂=1.50 in DMSO at pH 7; r₁=0.55, r₂=1.20 in aqueous DMSO; r₁=0.75, r₂ =1.30 in DMSO at pH 1.5; r₁=0.85, r₂=0.50 in aqueous solution at pH 7; r₁=1.10, r₂=0.70 in aqueous solution at pH 1.5. From these values Price's Q and e values, for SMAS were calculated, and it was found that they are 0.63 and 0.57 in DMSO at pH 7, and O.51 and O.55 in aqueous DMSO, 0.67 and 1.04 in DMSO at pH 1.5, O.23 and O.28 in aqueous solution at pH 7, and 0.27 and 0.69 in aqueous solution at pH 1.5 respectively. The large differences in reactivity of SMAS may be attributed to the different electron distributions in SMAS in each solvent which are caused by poor solvating power of dimethylsulfoxide and by the addition of protons. Homopolymerization of SMAS shows first-order dependence on the initiator concentration, and this is attributed to degradative chain transfer of SMAS. The rate of copolymerization of AN and SMAS decreases with increasing SMAS content. It has been found that there is a peculiar effect in the range of 8-12 mole % of SMAS monomer feed in aqueous solution which is in the transition state from homogeneous t heterogeneous phase.

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Polymerization of acrylonitrile (AN) in aqueous solution initiated by the redox system of ammonium persulfate (APS)-hydroxylamine hydrochloride (HA) has been investigated. The rate of polymerization could be represented by the following equation.
_??_
Chain transfer constant of HA was found to be 0.165.
The degree of whiteness of the polymer obtained by this system is excellent compared with other polymers obtained by different systems.

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he emulsion polymerization of methyl methacrylate (MMA) was carried out in a waterbath controlled at 70±0.3°C, using potassium persulfate (KPS) as an initiator and Rapisol (sodium dialkyl sulfosuccinate) as an anionic emulsifier. The effect of the following monomer-addition techniques on the time-temperature curve was examined:(A) initial addition of monomer, (B) portionwise addition of monomer, and (C) dropwise addition of monomer.
The time-temperature curve in the case of (A) was found to have a plateau region and a peak (similar to that for vinyl acetate discribed in the previous paper) even though reflux was not observed throughout the polymerization process.ΔT=T_max (temperature in the flask at the peak)-T_e (temperature of the reaction system in equilibrium with the water-bath at 70°C) increased with increasing concentration of KPS and amount of monomer, but it was not affected by the concentration of Rapisol. The time-temperature curve in the case of (C) varied with the rate of monomer-dripping.
From the data of polymerization rate per particle, changes of molecular weight of polymer and of monomer-polymer composition throughout the polymerization process, it was concluded that occurence of the peak is due to Trommsdorff effect. Considering Trommsdorff effect, ΔT is expressed as
_??_where V and N are the total volume of polymer particle at the peak in the time-temperature curve and the number of polymer particle in the entire system, respectively.

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The time-temperature curves for the emulsion polymerizations of various monomers in a water-bath controlled at a constant temperature were found to be classified into three groups (A-, B-, and C-types).
A-type is found in the case of T_a (azeotropic temperature of vinyl monomer-H₂O system)<T (temperature of the reaction flask). The curve consists of a plateau region (under reflux) and a peak (without reflux). The emulsion polymerizations of vinyl acetate at 70°C and of methyl acrylate at 74°C are representative examples.
B-type, whose time-temperature curve has only a weak peak, is observed when Trommsdorff effect is not remarkable during polymerization and T_a>T. The timetemperature curves for styrene, n-butyl methacrylate, and ethyl acrylate at 70°C are typical.
C-type is observed when Trommsdorff effect is remarkable during polymerization and T_a>T. The time-temperature curve has a plateau region (without reflux) and a peak (without reflux), the shape of which is similar to that of A-type in spite of no reflux. Typical examples are the emulsion polymerizations of methyl methacrylate and of ethyl methacrylate at 70°C.
A relationship among the above types of time-temperature curves was clarified by considering the integral heat of polymerization (sum of the heat evolved during polymerization up to that reaction time).
In the case that the addition technique, of monomer is carried out dropwise the time-temperature curves were also classified into three groups, which are different from the above types.
The effects of additives (solvent or non-solvent for vinyl polymer) on the time-temperature curve were examined.
The results mentioned above suggest several important factors for temperature-control in the emulsion polymerization of vinyl monomers.

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It is generally known that some vinyl monomers change to monomer peroxides and these peroxides initiate the polymerization of vinyl compounds. In this paper, the formation conditions of the monomer peroxide of methyl methacrylate (MMA) and the polymerization initiated by the MMA peroxide are discussed. The results obtained are as follows. 1) MMA peroxides formed in the course of the autoxidation of MMA are mainly the monomeric peroxides which contain hydroperoxides. The ratio of hydroperoxide to total peroxide which is formed by autoxidation in the dark at low temperature is near a half. 2) MMA peroxide formed by the bubbling MMA with oxygen at 50°C is mainly polyperoxide. The molecular weight of this peroxide is 1230, the structure is alternative copolymer of MMA and oxygen, and it contains a small amounts of hydroperoxide. 3) The rate of polymerization of MMA initiated by MMA peroxide is proportional to the squre root of the concentration of peroxide and the apparent energy of activation of polymerization is 16.6kcal/mole. Monomer peroxide is more effective in initiating polymerization than polyperoxide. 4) Many peroxides are found in the polymethyl methacrylate polymerized under the air atmosphere at 50°C.
From these results, it is reasonable to conclude that MMA peroxide formed by autoxidation of MMA could initiate polymerization of MMA and its behavior was similar to that of ordinary initiators such as BPO and AIBN, and moreover, monomer peroxide is more effective in initiating polymerization than polyperoxide.

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Homopolymerization and copolymerization of dihydroanisol (DHA) have been studied. Non-conjugated dihydroanisol (2, 5-DHA) homopolymerized easily with the use of cationic initiators such as Lewis acids but molecular weight of the polymer obtained was ratherlow. The polymer contains some carbonyl groups in the molecule and the content of the carbonyl groups increased by the treatment of the polymer with acids such as sulfuric acid. From these results it seems that 3, 4-addition occurred predominantly in this polymerization. Conjugated dihydroanisol (2, 3-DHA) was polymerized by cationic initiators and the polymer obtained also contained some carbonyl groups. Copolymers of 2, 3-DHA with styrene, acrylonitrile, methylmethacrylate and methacrylic acid were formed by radical initiators. Monomer reactivity ratios were as follows; 2, 3-DHA (M₁)-acrylonitrile (M₂), r₁=0.13±0.10, r₂=0.48±0.10 (at60°C); 2, 3-DHA (M₁)-styrene (M₂), r₁ =0.00±0.20, r₂=4.68±0.20 (at 60°C). Copolymerization of 2, 3-DHA with maleic anhydride took place readily without initiator.

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