Copolymerizatioonf styrene with methyl methacrylate in trimethylaminew as carried out with the use of alkali metals such as lithium, sodium, potassiuma nd cesiuma s an initiator. Styrene content in copolymero btainedw as greater than that in the case of ordinary homogeneous anionic copolymerization. The relations of styrene content with various copolymerization conditionsw ere examined. Styrene contenti n the copolymeirn creasedw ith increasing mole fraction of styrene in monomerm ixture, copolymerizationte mperature and catalyst concentration and decreased with increasing conversion. Styrene content obtained in the presence of sodium, potassium and cesium was greater than that in the case of lithium. From these results copolymerizationm echanismw as discussed

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Thermal stability of maleic anhydride-vinyl acetate copolymer was studied in a range of temperatures from 150 to 200deg;C by a flow method. Above 150deg;C the copolymer begins to decompose. Main volatile product is acetic acid, which amounts to weight loss. By assuming first order reaction with respect to weight loss, activation energies were determined as 42.6 kcal/mol in nitrogen and 28.4 kcal/mol in air. Analysis of the decomposed copolymer shows that both double bond and cross-linkage are formed more easily in nitrogen than in air, and that epoxy groups, however, are formed only in air. A degradation mechanism is suggested.

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The mechanical denaturation of poly-L-tyrosine in aqueous solutions by means of shearing force was studied. The experiment was carried out with a few shearing methods. The coagu ration of poly-L-tyrosine caused by shearing force was observed in the aqueous solutions of the pH range from 9.9 to 10.7.
These coagulated molecules were proved to have the β-structure by IR and X-ray diffraction methods. In Amide I region of IR spectra, these coagulated molecules give 1630 cm^-1 band, and X-ray diffraction patterns of those indicate presence of 4, 6 A reflection.
The process of the mechanical denaturation of poly-_L-tyrosine in aqueous solution can bc interpreted as that intramolecular hydrogen bonding in α-helical conformation changes into. intermolecular hydrogen bonding in β-structure by means of the shearing force. This result agrees with the process of the mechanical denaturation of poly--_L-glutamic acid in. aqueous solution.

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A method for evaluating the static electricity of polymer films is described. Only the generated charges by rubbing are measured by a special apparatus previously reported³⁾ . As the results of the analyses and observations about them, the apparent static electricity of a material (q_a) is defined by q_a=Q₁/Wr, where Q₁ is the generated charge by the first rubbing and indicates approximately the product of the saturated charge (Q_s) and the coefficient of charge-up-rate (α). These quantities are material constants concerning to the static electrification. Wr indicates the dependence of the Q₁ value on the rubbing normal force and γ is generally 1/2-1. The importance of the real contact areas affecting the apparent static electricity is discussed from the following facts; a) similarity of the static charge-distribution-patterns at produced by succeeded rubbing, b) the dependence of Q₁ values on the rubbing velocity is small, and it is negative with increasing the rubbing velocity, c) the dependence of the Q₁ values on the rubbing normal force is similar to that of the real contact areas. Therefore, the apparent static electricity (q_a) is considered as the product of the real static electricity (q_r) and the ratio of the real contact area to the apparent contact area (S₁) q_a=q_rS₁, where S₁ is the value at the firstrubbing under the unit normal force. Assuming some hypothesis on S₁, the estimated q_r values of polypropylene film are in a range of -10⁴ to -3esu/cm² by changing for 20 kinds of the rubbing materials from polyvinylalcohl film to high density polyethylene film.

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In the extrusion of molten Nylon 6 through a capillary, the shapes of melt fractured extrudates under various extrusion conditions were investigated. The melt fracture phenomena are observed in a characteristic shear stress range, which is dependent on the degree of polymerization of melt. Outside of this shear stress range, the melt fracture is not observed. The shapes of melt fractured extrudates are varied by shear stress. shear rate, degree of polymerization of melt, included entry angle and capillary diameter of the die. The maximum irregularity of melt fractured extrudates is observed at the critical shear stress. During melt fracture formation, the melt flow pattern is postulated as follow: at the entry of capillary, distribution of flow rate is eccentric and the frequency of fracture is 1×10⁸-3×10³ cycle/sec.

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In the course of melt spinning process of nylon 6 fiber, the shrinkage in the boiling water and longitudinal swelling of the fiber become minimum and maximum, respectively, at the spinning speed of 1500-2000 m/min. In order to explain the phenomenon the following assumptions were proposed:
1) During the melt spinning process, both the part of high orientation and the part of low orientation are formed in a single filament.
The former preferentially crystallizes and the latter remains uncrystallized.
2) The crystals caused by high orientation during the spinning have the fringed micell structure.
3) The amorphous part consists of loose and slack molecules, and at low spinning speed, it has the folded structure.
4) As the spinning speed becomes higher, the amorphous part transforms from the folded structure into the fringed structure. The spinning speed of 1500-2000 m/min is the transition speed between the two structures.
5) By boiling the sample, the crystal part elongates owing to the crystallization of the low oriented amorphous part adjacent to the crystalline paert and owing o the transformation from β-form to α-form, and the amorphous part shrinks proportionally to the degree of its orientation.

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Methacrylamide (MAAm), methacrylonitrile (MAN) and methacrolein (MAC) were polymerized using radical initiators, and the polymers obtained were converted to polymethacrylic acids (PMAA) and polymethyl methacrylates (PMMA). Stereoregulalities of these polymers were examined from view points of infrared absorption spectra of PMAA's and PMMA's, potentiometric titration curves and acid anhydride formation of PMAA's. Based on these results, the following conclusions were deduced that poly-MAAm's are relatively syndiotactic, poly-MAN's are atactic and the poly-MAC is relatively isotactic. Such differences of stereoregulalities between the polymers may be mainly due to the difference of steric hindrance of side groups of the starting monomers during polymerization. Furthermore, the PMMA derived from poly-MAC was observed to contained foreign structure which has not been clarified.

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When the polyethylene-terephthalate is isothermally crystallized from the molten state immediately or after quenching, its density increased with time through two processes (primary crystallization and secondary crystallization). In the secondary crystallization process the next relations exist.
1) Between density (d) and crystallization time (t) a equation, d=d0+B log t and when crystallization temperature (Te) is Tc≤220°C, d0, and B become as follows, _??_
The increase in d with time t is mainly caused by the thickening of crystal.
2) Between the interval of crystals (long period) and density, a relation _??_is, obtained where_??_, do and _??_, dt, are the average long period and density at to and t, respectively.
3) The density (d_p) and long period (L^t_p) in the equilibrium state at the temperature T_c, are written as follows _??_where dc, d3, and d are the density of crystal, the density of crystal surface and the average thickness of crystal surface, respectively.

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In the initial period (t₀) of the secondary crystallization process of a polymer with a low degree of crystallinity, the.distribution of lamellar thickness is assumed to be asymmetrical about the thickness L^* at the maximum value of distribution function of lamella, being more broadened on the thinner side than the thicker side. Then, L_t^*, T_m (Lt^*) and the relation between the crystallization temperature T_c, and Tm (L_t^*) are expressed by the next two groups of formulae in the two ranges of crystallization time respectively.
1)_??_
2)_??_
Where t^* is the time at which L₀^*=L_t, t^l at equilibrium state, B' the slope obtained from the relation between the density and the logarithm of crystallization time, L_o the average thickness of lamella, L₀^t the average long period at t₀, s the average thickness of surface region, d_e the density of crystal region, d_a the density of amorphous region, c. the surface free energy, ΔH_f the heat of fusion, T_m^o equilibrium melting temperature and K constant number.
The ratio (surface free energy)/(heat of fusion) =_??_ as a function of L is variable with time and is given by next equation._??_

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Polyvinyl chloride _??_ and monodisperse polystyrene _??_ were heat-treated near the glass transition temperature (T0) and their thermal behaviors were studied by the Differential Scanning Calorimetry (DSC).
For both polyvinyl chloride and monodisperse polystyrene which were heat-treated at the lower temperature than T0, double peaks appeared in DSC thermograms. The low temperature peak (T_gl) corresponded to the temperature of the heat-reatment and was independent to Mn. The high temperature peak (T_gh) was also affected by the heat-treatment. T_gl was observed easily in the low molecular weight samples with molecular weight distribution, and also it was observed for monodisperse polystyrene suitably heat-treated. The thermograms of the second scanning of the heat-treated sample is similar to the untreated one as the T61 disappeared by melting. The dependence of To on the rate of scanning was different from that of T_gl.
In the sample treated at T_g or higher temperature than T_g, only one endothermic peak appeared. The T_g of this sample was similar to that of untreated sample, but the shape of transition peak changed. The longer the time of treatment at T_g the higher the endothermic peak.
These results suggest that the difference of the enthalpy of transition between the heattreated and untreated sample is due to the different glassy state having different amounts of free volume or configurations. The double peaks are probably attributed to the co-exsistence of different glassy states in amorphous region. The low temperature transition corresponding to the treatment is due to the movement of mobile or unstable structure having a short relaxation time and the high temperature transition is due to the closely packed rigid chains.

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By the means of Differential Scanning Calorimetry (DSC), thermal behaviors were studied for linter cellulose, gel cellulose and amorphous cellulose over the range from 20°C to the decomposition temperature.
The glass transition temperatures (T_g) were 85°C and 55°C for linter cellulose and amorphous cellulose, while in the case of gel cellulose T_g could not be determined because endothermic deviation above T_g was cancelled by the starting of exothermic effect. The glass transition temperatures of various samples of cellulose under the state containing moisture (55% RH) were determined as 58°C, 58°C and 57°C for linter, gel and amorphous cellulose respectively. No lowering of T_g for amorphous cellulose by water absorption can be explained to be due to the increase of hydrogen bond.
Exothermic peaks were detected in the range 80-150°C for gel cellulose and 100-180°C for amorphous cellulose. No exothermic peak was found in linter cellulose. The heat evolved became smaller by the longer heat treatment near T_r But more pronounced decreasing of the heat was observed by the treatment at the temperature higher than 100°C. The effect of heating time was also found in these tem
The infrared spectra of amorphous cellulose was measured in the heating cell and it was found that the optical density of the band 1590 cm^-1 appeared with increasing temperature The variation of the band of 1590 cm^-1 coresponded to that of the exothermic peak of the thermogram.
Comparing with the IR spectra, the exothermic peak was, attributed to the increase of the hydrogen bonding. The evolved heat calculated from the thermogram of amorphous cellulose was about 2 cal/g, and so one hydrogen bond in 10 pyranose rings was related to this transition.
Viscoelastic behavior was also measured for amorphous cellulose. In the heating curve from room temperature to 190°C, two maximum of tan δ were found at 35°C and 130°C. In the cooling curve, the lower transition temperature shifted to higher temperature and the higher transition diappeared. So the viscoelastic behaviors corresponded well to the thermal behavior.

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The molecular motion of the unstretched film of poly (vinylidene fluoride) was studied by means of dielectric and dynamic mechanical measurements and broad line NMR.
Four relaxation processes are found in the dielectric behaviors, and they are named α, β, γ and δ dispersion with decreasing temperature. Probably α-dispersion may be attributable to the melting of the crystalline region, though the loss maximum couldnot be observed in our experiment. It was deduced with the aid of the results of NMR that β-dispersion observed at about 80°C may be due to small-scale molecular motioriin the crystalline region γ-dispersion at about -40°C is assigned to the Micro-Brownian motion of the molecular chain in the amorphous region.δ-dispersion at about -70°C seems to be due to the local oscillation of molecular chain. The apparent activation energies of β-, γ-, and δ-dispersions are 21 kcal/mole, 29 kcal/mole, and 6 kcal/mole respectively.

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Effects of molecular weight and branching on the melt index (MI) and intrinsic viscosity number of unfractionated high pressure polyethylene were studied quantitatively for many samples of polyethylene selected systematically and the following experimental equation was obtained:
_??_
Where M^w is the weight average molecular weight, and g is a parameter of branching. The relationship between intrinsic viscosity number and melt index shows that the intrinsic viscosity becomes higher with increasing branching in the polyethylene samples even in the case having equal MI.

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