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Agrammatism is one of the core clinical features of non-fluent/agrammatic variant primary progressive aphasia, and it has traditionally been considered the hallmark of non-fluent aphasia in Western countries. However, agrammatic speech may remain undetected in Japanese patients because of the agglutinative structure of the language and high flexibility in word order. In the present study, we aimed to analyze agrammatism in the speech production of Japanese patients with aphasia due to neurodegenerative disease using an anagram test generated by our laboratory. Four patients were recruited from the dementia clinic at Tohoku University Hospital between December 2014 and August 2015: two patients with non-fluent/agrammatic variant primary progressive aphasia, one with semantic variant primary progressive aphasia, and one with probable Alzheimer's disease experiencing episodic memory impairment accompanied by transcortical sensory aphasia. All patients underwent thorough neurological and neuropsychological testing before performing a Japanese anagram task based on the Northwestern Anagram Test. Our findings indicated that the two patients with non-fluent/agrammatic variant primary progressive aphasia exhibited poorer performance on the anagram task than the remaining two patients. Therefore, the anagram test used in the present study may aid in detecting output aspects of agrammatism in Japanese patients with aphasia, although future studies are required to develop a standardized version of test.

Key Clinical Message NOMI is mesenteric hypoperfusion with reactive vascular spasms. Changes in the color of the mucosa may reflect the severity of the ischemia of the colon and the severity of prognosis. Even with surgery, the mortality rate is 75%. Diagnosis requires a high degree of clinical suspicion.

A 78-year-old woman was admitted to another hospital with vomiting. Chest X-ray showed an abnormal shadow in the lower right lung field, and CT indicated a Morgagni hernia containing the stomach and transverse colon. The patient was transferred to our hospital and underwent laparoscopic surgery. After the hernia contents were repositioned into the abdominal cavity, we repaired the hernia orifice with a prosthetic mesh to achieve a tension-free repair. There were no complications after the surgery, and there has been no recurrence. The patient has remained free of clinical symptoms since 10 months after the surgery. Laparoscopic repair with a prosthetic mesh for Morgagni hernia is a simple and safety procedure for elderly patients.

Skin hyperpigmentation disorders as a result of abnormal melanin production induced by ultraviolet (UV) irradiation are both a clinical and a cosmetic problem. This melanin production is mediated by tyrosinase whose expression is positively regulated by microphthalmia-associated transcription factor (MITF). We recently found that expression of heat shock protein 70 (HSP70) inhibits melanin production. In this study, we searched for HSP70 inducers from Chinese herbs and selected an ethanol extract of Eupatorium lindleyanum (E. lindleyanum). Not only melanin production but also the activity and expression of tyrosinase were significantly suppressed in cells treated with E. lindleyanum extract as well as in HSP70-overexpressing cells. The expression of MITF was clearly suppressed in cells treated with E. lindleyanum extract but not in HSP70-overexpressing cells. These results suggest that E. lindleyanum extract suppresses the expression of tyrosinase and melanin production through both HSP70-dependent and HSP70-independent mechanisms.

Poly(phenylsilyne) and poly(phenylgermyne), which have a network Si- and Ge-skeleton, were synthesized by electrochemical reduction of trichlorophenylsilane and trichlorophenylgermane, respectively. The poly(phenylsilyne) showed broad absorption and emission bands that are characteristic of silicon network polymers. Similarly broad absorption and emission bands were observed for the poly(phenylgermyne). Radical anions and radical cations of poly(phenylsilyne) and poly(phenylgermyne) were produced by pulse radiolysis. The radical ions of these network polymers showed broad transient absorption bands from the UV to the IR region. Within 200 ns after pulse radiolysis, the absorption band of the radical cation in the UV region decreased, whereas the band in the IR region increased. The time-dependent spectral change of the radical cation suggests the formation of a change resonance band of the delocalized positive charge on the σ-conjugated polymer chain. In contrast to the radical cation, the radical anion of the network polymers did not show a spectral change.

Ring-opening radical polymerization has been followed by the flash photolysis method. As an initiator radical, the arylthiyl radical (ArS˙) was used; the addition reaction rate constants of ArS˙ to vinyl monomer containing epoxy-ring such as vinyloxiranes have been determined at first. The rate constant of ring opening reaction of the adduct radical changing to ArSCH2CH CROCH2˙ were determined in the form of the relative values, which were converted to the absolute values. The ring-opening reaction rate constants were ca. 106 s−1, which indicates that the ring-opening rates are faster than usual radical propagation rates. The rate constants for vinyl monomer with 5-member ring (1,4-epoxy-1,4-dihydronaphthalene) were similarly evaluated.

To assess the extent of overdiagnosis bias in lung cancer screening, clinical Stage I lung cancer cases detected by chest radiograph examination, with histologic or cytologic evidence of malignancy and not treated by surgical operation, were followed up for more than 10 years. Of 1297 screen-detected and 1297 symptom-detected cases collected from 20 institutions, 42 screen-detected and 27 symptom-detected cases satisfied the study criteria. In about half of the cases, the patients had no contraindication for surgical treatment, but they refused surgical procedure. All such patients from the screen-detected and symptom-detected groups died within 122 and 67 months, respectively, of diagnosis. Among the screen-detected and symptom-detected cases, 80% and 81%, respectively, of the patients died of lung cancer. The median survival time was 25 and 13 months for those in the screen-detected and symptom-detected groups, respectively. The difference in survival was statistically significant between the two groups, which indicated the effect of lead time and length-biased sampling. Analysis of the causes of death other than lung cancer showed that there was no difference in the observed cumulative rates of deaths of other causes between the two groups, and these figures were almost the same as those expected from the general population. This indicates that overdiagnosis bias would be minimal in screen-detected lung cancer cases detected by chest radiograph examination.

On heating films of long-chain alkylamino-1,3,5-triazine-2,4-dithiols, substituted with unsaturated groups in the 6-position, on copper plates in air, the films become partially insoluble in benzene. The polymerization rate and monomer conversion increased with temperature above 80°C and with time. At low temperatures, an induction period was observed. The detailed behavior was dependent upon the number and length of the alkyl chains. Films with high packing density polymerized more slowly. In the presence of azobis(isobutyro)nitrile (AIBN) and benzoyl peroxide (BPO), the rate and conversion increased and the induction period disappeared. The optimum concentration of initiators was approximately 0.0025 mol% of monomer. The polymerization of the films was initiated by oxygen activated with copper, or by radicals derived from AIBN and BPO. It is proposed that the growth of polymer proceeded mainly by the addition of thiyl radicals to unsaturated groups, the insoluble polymers being formed by the coupling of thiyl radicals.

Ring-opening radical polymerization has been followed by the flash photolysis method. As an initiator radical, the arylthiyl radical (ArS˙) was used; the addition reaction rate constants of ArS˙ to vinyl monomer containing epoxy-ring such as vinyloxiranes have been determined at first. The rate constant of ring opening reaction of the adduct radical changing to ArSCH2CH CROCH2˙ were determined in the form of the relative values, which were converted to the absolute values. The ring-opening reaction rate constants were ca. 106 s−1, which indicates that the ring-opening rates are faster than usual radical propagation rates. The rate constants for vinyl monomer with 5-member ring (1,4-epoxy-1,4-dihydronaphthalene) were similarly evaluated.

Three cases of occult thyroid cancer measuring 10, 6, and 3 mm in diameter were discovered by fine-needle aspiration cytology of cervical lymph nodes. In these three cases, thyroid tumors were not palpable, and scintigraphic, echographic, and soft-tissue radiologic examinations demonstrated no abnormalities of the thyroid glands. Cytologically, the presence of intranuclear cytoplasmic inclusions, nuclear grooves, and colloid was characteristic in aspirated materials. Histologically, all three cases were diagnosed as papillary carcinoma. Fine-needle aspiration cytology of cervical lymph node was very useful to find occult carcinoma of the thyroid gland.

Lung cancer risk among exsmokers according to years since cessation of smoking was assessed by means of a case-control study. The case series consisted of 1,052 lung cancer patients who were newly diagnosed and admitted to eight hospitals in Osaka in 1986-88. Smoking histories were compared with those of 1,111 controls admitted to the same hospitals during the same period without any diagnosis of smoking-related disease. The odds ratio of lung cancer for exsmokers compared to current smokers was estimated to be 0.90, 0.50, 0.51, 0.59, 0.48 and 0.29, for 1-4, 5-9, 10-14, 15-19, 20-24 and greater than or equal to 25 years after cessation of smoking, respectively. Risk reduction appeared to be greater for those who smoked less than the 1200 cigarette index, compared to those who smoked more. In classification according to histologic type, small cell and large cell carcinoma showed a rapid decrease compared to adenocarcinoma, while squamous cell carcinoma showed an intermediate pattern. Quantitative estimates for reduction of lung cancer risk among exsmokers can be used for projecting lung cancer incidence in the future, by assuming future trends of smoking prevalence, as well as for health education among individual smokers.

A new dual-parameter of vinyl monomers for the reactivities toward free-radicals has been evaluated on the basis of kinetic data obtained by the flash photolysis method. As a model reaction system, the reversible addition reactions of the substituted phenylthiyl radicals to vinyl monomers are selected. The absolute rate constants and the relative equilibrium constants for these reactions have been determined. The Hammett reaction constants (ρ) for the addition reaction rates were evaluated by the variation of the substituents at the para-position of the arylthiyl radicals. From the values, the polar parameters (P- values) have been evaluated. The P values of various vinyl monomers correlate with the e values of the Q-e scheme proposed by Alfrey and Price. The resonance stabilization terms of the propagating radicals were evaluated from the equilibrium constants (K) which correlate with the Q values. The K-P dual-parameter can be used in order to predict the reactivities of vinyl monomers for the primary radicals (initiation step). The monomer reactivities from the copolymerization data are also correlated with the dual parameter. There are some advantages in the new dual-parameter compared with the Q-e scheme; the separation of the resonance term from the polar term is complete and the steric factor is not included in the polar term.

The spreading behaviour of preformed poly(N-alkylacrylamides) having hexyl (PHA), octyl (POA), decyl (PDA), dodecyl (PDDA), tetradecyl (PTDA), hexadecyl (PHDA), and octadecyl (PODA) substituents on a water surface, and the properties of the Langmuir-Blodgett (LB) films deposited from these polymer monolayers were investigated. The surface pressure (F)-area (A) isotherms of the polymer monolayers were changed by the chain length of the substituents and the subphase temperature. The optimum conditions for the formation of a stable condensed monolayer from the polymer series of similar molecular weight (c. 4 × 103) were found when the alkyl substituent was the dodecyl group (i.e. PDDA) and the subphase temperature was 19°C. The condensed monolayers of PDA, PDDA, and PTDA could be transferred successively on to solid supports such as quartz slides, giving the Y-type uniform polymer LB films. The successive uniform depositions of PDDA monolayer up to 320 layers were confirmed by a relationship between the absorbance at around 200 nm due to carbonyl group and the number of layers deposited. The thickness of PDDA monolayer in the LB film was 1.72nm which agrees with the length of the dodecylamide substituent. F-A isotherms, FTIR, and X-ray diffraction measurements support that the polymer main chains are laid horizontally on the water surface and the alkyl substituents are oriented perpendicular to the chain in the condensed monolayer (see Scheme 1).

Sputum cytology was performed in 179 cases of squamous-cell carcinoma of the lung; 134 cases were diagnosed as positive. There were no significant differences in diagnostic accuracy of sputum cytology between tumors sizes. In cases with tumors extending proximally into the main, lobar, or segmental bronchi, the diagnostic accuracy of sputum cytology was significantly higher than in cases where the proximal invasion of tumor was limited to the peripheral bronchi. In cases with tumors 3 cm or less in diameter, when tumors extended proximally into main, lobar, or segmental bronchi, the diagnostic accuracy of sputum cytology was significantly higher than in cases with tumors extending proximally into subsegmental or subsubsegmental bronchi. In peripherally located squamous-cell carcinoma, in cases in which the tumor arose in subsegmental or subsubsegmental bronchi, carcinoma could be detected by sputum cytology even when it was roentgenographically occult.

The transient diaryl disulfide radical anions (RSSR−) were produced in nonaqueous solutions at room temperature by the flash photolysis of a solution of arylthiolate ion pair in the presence of the excess corresponding disulfide. The transient spectra were almost identical with those obtained from γ-radiolysis of the disulfides in 77 K 2-methyl-tetrahydrofuran (MTHF) glassy matrix. The spectra of disulfide radical anions in nonaqueous solutions were changed by cations, solvents, and para-substituents depending on the ion pair properties. The tighter ion pairs showed a shift of absorption band to the shorter wavelength. The disulfide radical anions decay by a unimolecular dissociation reaction to yield thiolate anion and thiyl radical. The decay kinetics were first-order in the initial time region. The rate constants obtained were changed by the counter cations in the order Na+ > K+ > Cs+ > Li+, and by solvents. The tighter ion pairs of the disulfide radical anions showed faster dissociation reaction. This is due to stabilization of a transition state with the counter cation.

A case of renal cell carcinoma (RCC) presenting various histologic growth patterns, including papillary, tubular and solid arrangements, and an area resembling sarcoma are described. In order to identify RCC of high versatility of renal carcinosarcoma, electrophoretic studies of tissue alkaline phosphatase (Al-P) and gamma-glutamyl transpeptidase (gamma-GTP), as well as histochemical studies of these enzymes, were conducted. The Al-P was proved to be bond type alone and the gamma-GTP corresponded with the novel isozyme associated with RCC tissue. Moreover, these two enzymes were found to be distributed in every part of different histologic appearance. It was concluded from these results that the histologic pleomorphism of the case herein reported was due to morphologic transformation of the neoplastic cells sharing essentially identical enzymatic nature.

A kinetic study has been made of polymerization of methyl methacrylate initiated by an electron donor–acceptor complex of liquid SO2 (electron acceptor) and nicotine (donor) in the presence of carbon tetrachloride. It is concluded that the polymerization proceeds through free-radical intermediates similar to the cases of liquid SO2–pyridine and liquid SO2–poly(2-vinylpyridine) complexes. The overall rate of polymerization is proportional to the square root of both liquid SO2 and nicotine concentrations, and the values of kp/kt½ under various polymerization conditions are in satisfactory agreement with the literature values. For the activation energy of initiation, 13.6 kcal/mole is estimated from the kp/kt½ values obtained at temperatures ranging from 0 to 80°C.

The absolute rate constants for reversible addition of the substituted phenylthio radicals to vinylpyridines in solution at 23°C have been determined by flash photolysis method. For each phenylthio radical, the reactivities of vinylpyridines is 3–5 times lower than that of styrene. The relative equilibrium constants estimated with flash photolysis indicate that the stabilities of the adduct carbon-centered radicals generated from vinylpyridines are similar to that from styrene. The Hammett plots suggest that the difference in the reactivities originates in the polar transition state; the nitrogen atom in 4-vinylpyridine withdraws the electrons of vinylic double bond.

Free radical copolymerization of sulfur dioxide with phenylacetylene (PA) in o-dichlorobenzene was studied in a range of temperatures from 30 to 80oC as a function of total monomer concentration ([SO2] + [PA]). PA content in the copolymers increases with decreasing total monomer concentration and increasing temperature. Mw/Mn becomes sharper with decreasing the total monomer concentration, but does not depend upon feed compositions which are changed keeping total monomer concentration constant at 2, 4, and 6 mol/L, respectively. These results strongly indicate the existence of depropagation. Thermal decomposition of the copolymers happens more easily than PA homopolymer and the carbon-centered free radicals are detected during the decomposition. Reactivity of ∼ CHĊ(Ph) free radical (∼ PA · ) is also discussed.

Free radical copolymerization of SO2 with 1-alkynes (AY) was studied by evaluation of the copolymerization rate under controlled conditions of copolymerization temperature and monomer concentration product ([AY][SO2]). The poly(alkyne sulfone)s always contained equimolar units of SO2 and alkyne, regardless of the copolymerization conditions. Using 1-hexyne (HY) and 1-octyne (OY) as comonomers of SO2, the values of ceiling temperature (Tc) were determined: when [HY][SO2] = [OY][SO2] = 0.25 mol2/L2, the values of Tc were 90.5 and 84.5°C, respectively. Tc increases with increasing monomer concentration product. The activation energies for propagation (Ep) and depropagation (Ed) of the SO2-alkynes copolymerization system were investigated, using the SO2OY copolymerization system, and estimated to be 12.2 and 26.7 kcal/mol, respectively. The value of Ed is high compared with that of the copolymerization of SO2 and 1-butene (20.3 kcal/mol), demonstrating that the free radical endings (∼ OYSO2 and ∼ SO2OY) are difficult to depropagate, compared with those formed from the copolymerizaton of SO2 and 1-butene. ΔS and ΔHp, calculated from experiments, were found to be −37.7 cal/mol K and −14.3 kcal/mol, respectively

Partially metallated polymers of 2-vinylfluorene in tetrahydrofuran THF and THF-dimethoxyethane mixtures were studied by electronic absorption spectroscopy. Effects arising from interaction of the ion pairs within the polymer chain were clearly observed. Conversion of the contact ion pairs with lithium and sodium cations into the solvent-separated ion pairs is influenced by interactions between the solvent-separated ions pairs. The polymer carbanions with bulky K+ and Cs+ cations exhibited a shift of λ with increasing carbanion concentration, suggesting the formation of an extended polymer chain in solution.

The kinetic behavior of the thiyl radical in the solution containing polyisoprenes and polybutadienes has been studied by the flash photolysis method. For benzothiazole-2-thiyl radical, the addition rate constants toward these polymers and the model compounds of the polymers were evaluated. The relative reverse rate constants and equilibrium constants were also estimated. The addition rate constants decrease with an increase in the degree of polymerization; the ratio of the addition rate constant for polyisoprene (3.1 × 104M−1 s−1 (in monomer unit); Mv = 674,000) to that for 2-methyl-2-butene (1.5 × 105M−1 s−1) is about 1/5. This indicates that the polymer chain effect appears in the free-radical addition reaction. The relative reverse rate constants for the polymers are also smaller than those for 2-methyl-2-butene, suggesting a kind of polymer effects; i.e., it can be presumed that the bonded-thiyl radicals migrate very rapidly to the neighboring double bonds in the polymer. Significant differences in the rate parameters were observed between polyisoprene and polybutadiene, between cis- and trans-polyisoprenes, and between 1,4- and 1,2-polybutadienes.

The transient diaryl disulfide radical anions (RSSR−) were produced in nonaqueous solutions at room temperature by the flash photolysis of a solution of arylthiolate ion pair in the presence of the excess corresponding disulfide. The transient spectra were almost identical with those obtained from γ-radiolysis of the disulfides in 77 K 2-methyl-tetrahydrofuran (MTHF) glassy matrix. The spectra of disulfide radical anions in nonaqueous solutions were changed by cations, solvents, and para-substituents depending on the ion pair properties. The tighter ion pairs showed a shift of absorption band to the shorter wavelength. The disulfide radical anions decay by a unimolecular dissociation reaction to yield thiolate anion and thiyl radical. The decay kinetics were first-order in the initial time region. The rate constants obtained were changed by the counter cations in the order Na+ > K+ > Cs+ > Li+, and by solvents. The tighter ion pairs of the disulfide radical anions showed faster dissociation reaction. This is due to stabilization of a transition state with the counter cation.

Intramolecular excimer formation in poly(styrene sulphone)s with various compositions has been investigated based on the characteristic monomer sequence distributions which were determined experimentally. The fluorescence spectra of the poly(styrene sulphone)s show two emission bands at 285 nm and 330 nm as for polystyrene, corresponding to the monomer and the excimer bands, respectively. The ratio of the excimer to the monomer emission intensities (Ie/Im) is linearly correlated with the mole fraction of styrene. This observation is a consequence of the characteristic sequence distributions in poly(styrene sulphone)s. containing a very small fraction of SMS units (S = SO2; M = styrene). The efficiency of excimer formation in poly(styrene sulphone)s with regular styrene sequences, e.g. dyad sequence only, was calculated from the sequence distribution and empirical Ie/Im. It is concluded that the excimer formation in poly(styrene sulphone)s is very efficient. Energy migration along the copolymer chain was also demonstrated by measuring the degree of polarization as a function of copolymer composition. The efficient excimer formation and the depolarization in poly(styrene sulphone)s suggest that the SO2 unit in poly(styrene sulphone)s does not act as a barrier or trap to energy migration unlike the methyl methacrylate unit.

For olefins containing aromatic groups such as naphthyl, monomer reactivities have been evaluated on the basis of the absolute rate constants and relative equilibrium constants which were determined by the flash photolysis method using phenylthiyl radicals as attacking radicals. The rate constant for addition of α-methyl-1-vinylnaphthalene is lower than that of α-methyl-2-vinylnaphthalene. This suggests that the aromatic π-orbital; of the 1-naphthalene derivative are twisted away from the olefinic π-orbital; in the transition state, the delocalization of the unpaired electron on the olefinic carbon into the naphthyl group is reduced by the angular structure. For such twisted monomers, the dihedral angles between the aromatic π-orbitals and the olefinic π-orbital have been estimated by comparing the observed rate constants with the reactivity indexes calculated by the molecular orbital method. In the case of α,β-disubstituted olefins, the rate constants are lower than those of α,α-disubstituted ones; this suggests that the approach of the phenylthiyl radical is impeded. New reactivity parameters were evaluated for the monomers with bulky groups.

The cytologic study of the effect of chemotherapy was performed in oat-cell carcinoma of the lung. Cellular characteristics of tumor cells obtained by brushing via bronchoscopy were compared between responders (13 patients in complete and partial regressions) and nonresponders (13 patients with no response) treated with cyclophosphamide. The tumor cells in the responders more frequently showed finely granular chromatin evenly distributed throughout the nuclei. The tumor cells in nonresponders showed predominantly either deeply stained nuclei with coarsely granular chromatin distributed evenly or pale nuclei with unevenly distributed chromatin. These findings were also applied in the evaluation of the effect of combination chemotherapy. The nuclear chromatin pattern from oat-cell carcinoma of the lung may be an indicator to predict the degree of response to chemotherapy.

A study has been made of the effect of dimethylaniline on the polymerization of styrene, methyl methacrylate, butyl acrylate, vinyl chloride, and acrylonitrile initiated by 2,2′-azobisisobutyronitrile at 50°C. It was found that the rate of polymerization decreased with addition of dimethylaniline, but the rate of decomposition of 2,2′-azobisisobutyronitrile remained constant. The chain transfer constants for the polymerization of these monomers were determined according to Mayo's equation. It was observed that the values of the chain transfer constant for dimethylaniline were proportional to those of the retardation by the latter. From these results, it is assumed that the decrease in rate of polymerization by addition of dimethylaniline is due to the chain transfer reaction.

The cationic polymerization of styrene in liquid sulfur dioxide was conducted at −10°C. in the presence of hydrocarbons such as benzene, toluene, p-xylene, p-cymene anisole, cyclohexane, and chlorobenzene diluted with carbon tetrachloride and with boron trifluoride etherate as catalyst. When aromatic hydrocarbons were added to the polymerizing system in liquid sulfur dioxide, both overall rate and degree of polymerization decreased with increasing of hydrocarbon concentration. On the other hand, the rate and degree of polymerization increased as the concentrations cyclohexane or chlorobenzene added increased. When anisole was used, polymerization was completely inhibited. The order of solvent participation n on the polymerization in liquid sulfur dioxide was obtained. The magnitude and the sign of n is discussed and explained by interaction of the added solvent with the active carbonium ion of the growing chain and with liquid sulfur dioxide.

p-Bromostyrene, p-methylstyrene and α-methylstyrene were subjected to polymerization in liquid sulfur dioxide with α,α'-azobisisobutyronitrile as an initiator at polymerization temperatures of 0–60°C. In case of polymerization of p-bromostyrene, only polysulfones of 1:2 molar ratio between sulfur dioxide and p-bromostyrene were obtained. No cationic polymerization was observed. In case of polymerization of p-methylstyrene polysulfone having 1:2 composition, a radical polymerization product, as well as poly-p-methylstyrene, a cationic polymerization product, as obtained, revealing concurrent and competitive occurrence of both polymerizations. The cationic polymerization was explained as the result of the electron-donating property of the para-methyl substituent and the catalytic action of sulfur dioxide or sulfurous acid formed with a minute amount of water contained in liquid sulfur dioxide. In liquid sulfur dioxide, the cationic polymerization was perfectly inhibited by DMF and the radical polymerization was not affected by the presence of DMF. In a system in which the radical polymerization alone proceeded in liquid sulfur dioxide, the overall rate of the polymerization was proportional to the concentration of AIBN in the order of 0.7. This was interpreted to indicate that the strong solvation between sulfur dioxide and the terminal radical of the growing radical due to hyperconjugation of the p-methyl group may stabilize the terminal radical, leading to a unimolecular termination. In the polymerization of α-methylstyrene, the addition of AIBN did not give polysulfone, but gave poly-α-methylstyrene alone as a result of cationic polymerization.

The effect of liquid sulfur dioxide concentration on cationic copolymerization of styrene (M1) with methyl acrylate (M2) was carried out with the use of boron trifluoride–ether complex as a catalyst. The reaction was carried out at 0°C. The monomer reactivity ratios r1 and r2 increased with increase in liquid sulfur dioxide concentration, and r1 was changed from r1 = 0.30 at [liq. SO2]0 = 6.58 mole/l., to r1 = 1.50 at [liq. SO2]0 = 13.16 mole/l., but r2 was not changed. These facts indicated that reactivity of carbonium ion of styrene in the propagation step was increased with increasing liquid sulfur dioxide concentration. The relation between the overall rate of copolymerization and liquid sulfur dioxide concentration is the same as in the case of the cationic homopolymerization of styrene, and polymolecular contribution of liquid sulfur dioxide on the overall copolymerization is shown from these observations.

Radical polymerization of acrylonitrile in liquid sulfur dioxide was carried out at 50°C. with α,α-azobisisobutylonitrile as an initiator. When aniline (An), dimethylaniline (DMA), dimethyl-o-toluidine (DMoT), and diethylaniline (DEA) were added to this system, it was found that each base acted as a retarder for the polymerization. When the chain transfer constant was calculated for each base, the values were 1.0 (An), 1.5 (DMA), 3.0 (DMoT), and 9.3 (DEA). The Alfrey-Price etr values calculated from these values were −2.79 (An), −3.14 (DMA), −3.72 (DMoT), and −4.66 (DEA). On plotting these values against pKa of each base, a linear relationship was found.

The polymerization of methyl methacrylate can be initiated by a charge-transfer complex of liquid sulfur dioxide and pyridine in the presence of carbon tetrachloride. The molar ratio of sulfur dioxide and pyridine which participated in the complex was found from a spectrophotometric study to be 2:1. The polymerization proceeds through free-radical intermediates. The overall rate of polymerization is proportional to the square root of the concentration of the complex, and the values of kp/kt1/2 under the various polymerization conditions were satisfactorily consistent with the literature value. For the activation energy of the overall reaction, 8.2 kcal./mole was obtained, and for initiation, 9.7 kcal./mole was evaluated from the values of kp/kt1/2. It was deduced from a kinetic mechanism for the initiation that a primary radical may be produced from the reduction of carbon tetrachloride by an associated complex consisting of liquid sulfur dioxide–pyridine complex and the monomer.

The radical terpolymerization of sulfur dioxide, hexene-1, and methyl acrylate has been investigated, and from the dilution effects on composition of the terpolymer it would seem reasonable to rule out the possibility of the participation of the charge-transfer complex in the propagation process. We have also carried out terpolymerization of sulfur dioxide, hexene-1, and methyl methacrylate and obtained a terpolymer having the block nature.

A polymerization was induced with a charge-transfer type of complex consisting of styrene and maleic anhydride in the presence a solvent such as ethyl benzene, cumene, or p-cymene. No polymer was obtained either when the solvent was missing from the polymerization system or when benzene, toluene, or xylene, which are relatively stable to hydrogen abstraction, was added to the polymerization system. An effective initiation, however, took place when cumene or p-cymene, each of which has a labile hydrogen on an α carbon, was added. On the basis of elementary analysis and infrared spectroscopy the formation of copolymer containing substantially equimolar amounts of styrene and maleic anhydride was ascertained. This polymerization was inhibited by the addition of DPPH, suggesting that the system styrene–maleic anhydride–cumene functions much as a conventional free-radical initiator. On the other hand, when a solution of cumene and liquid sulfur dioxide was added to the polymerization system, polystyrene was obtained. This polymerization was inhibited by the addition of a base such as dimethyl-formamide or dimethyl sulfoxide, indicating that the polymerization proceeds through carbonium ion intermediates. The addition of ethyl benzene or of p-cymene brought about the same result as cumene. It is conceivable that the polymerization is induced by the abstraction of hydrogen attached at the α position of cumene by means of the charge-transfer complex of styrene and maleic anhydride.

The polymerization of methyl methacrylate can be easily initiated in systems containing poly-2-vinylpyridine (polymer electron donor), liquid sulfur dioxide (acceptor), and carbon tetrachloride. The various types of polymer electron donors and acceptors which range widely in their electron affinity were also examined. The addition of DPPH causes the retardation; a decrease in the poly-2-vinylpyridine concentration or an increase in the monomer concentration leads to a higher molecular weight of poly-MMA. The values of kp/√kt obtained under the various polymerization conditions are satisfactorily consistent with the literature values, suggesting that the polymerization proceeds through free radical intermediates. Die Polymerisation von Methacrylsauremethylester kann in Systemen, die Poly-2-vinylpyridin (als polymerer Elektronendonator), flussiges Schwefeldioxid (als Acceptor) und Tetrachlorkohlenstoff enthalten, leicht initiiert werden. Verschiedene Arten von polymeren Elektronendonatoren und -acceptoren mit einem grosen Bereich der Elektronenaffinitat wurden ebenfalls untersucht. Der Zusatz von DPPH bewirkt eine Verzogerung der Polymerisation; eine Verminderung der Poly-2-vinylpyridin-Konzentration oder eine Erhohung der Monomerenkonzentration ergibt ein hoheres Molekulargewichtes. Die unter den verschiedenen Polymerisationsbedingungen erhaltenen Werte von kp/√kt stimmen mit den in der Literatur angegebenen Werten befriedigend uberein und weisen darauf hin, das die Polymerisation uber freie Radikale verlauft.

Only polymethyl methacrylate was obtained and polysulfone was not produced when radical polymerization of methyl methacrylate was carried out in liquid sulfur dioxide. When acrylonitrile (AN) with methyl methacrylate (MMA) and with α-methylstyrene (αMST) were copolymerized respectively, the copolysulfones were not obtained. Liquid sulfur dioxide acted only as a solvent. The following monomer reactivity ratios were obtained: r1 (AN) = 0.09 ± 0.05, r2 (MMA) = 1.01 ± 0.07: r1 (AN) = 0.08 ± 0.03, r2 (αMST) = 0.25 ± 0.06. Tetraethyl ammonium bromide (TEAB) were added to these copolymerization systems to see that there is almost no change in the values of r1's and r2's. Also no change was observed in the fraction of acrylonitrile and styrene in the copolymer formed with or without added TEAB when the radical copolymerization of AN and styrene in liquid sulfur dioxide was carried out. It was therefore made clear that the effect of TEAB on the radical polymerization of acrylonitrile in liquid sulfur dioxide was acting principally on the termination step. Bei der radikalischen Polymerisation von Methylmethacrylat in flussigem Schwefeldioxyd wird nur Polymethylmethacrylat, aber kein Polysulfon erhalten. Auch bei der Copolymerisation von Acrylnitril (AN) mit Methylmethacrylat (MMA) oder mit α-Methylstyrol (αMST) erhalt man keine Copolysulfone; flussiges Schwefeldioxyd wirkt nur als Losungsmittel. Folgende Copolymerisations-Parameter wurden erhalten: r1 (AN) = 0,09 ± 0,05, r2 (MMA) = 1,01 ± 0,07: r1 (AN) = 0,08 ± 0,03, r2 (αMST) = 0,25 ± 0,06. Zusatz von Tetraathylammoniumbromid (TEAB) zum Copolymerisationssystem ruft keine Anderung der r1- und r2-Werte hervor. Auch sind die Acrylnitril- und Styrolfraktionen im Copolymeren bei der radikalischen Copolymerisation von AN und Styrol in flussigem Schwefeldioxyd unabhangig von einem TEAB-Zusatz, was darauf schliesen last, das TEAB prinzipiell die Kettenabbruchreaktion beeinflust.

The radical polymerization of acrylonitrile was carried out in liquid sulfur dioxide and in benzene, with addition of aniline, dimethylaniline, dimethyl-0-toluidine, and diethylaniline to these systems. The temperatures of polymerization were 40, 50, and 60°C. It was found that the chain transfer reaction occurs more easily in liquid sulfur dioxide than in benzene; this was attributed to the differences in the polarity of the terminal radical of the growing chain in both solvents. The difference of activation energies due to the difference of bases is not so large. The frequency factors are rather important in both solvents for chain transfer reactions. The isokinetic relation is also discussed.

Copolymerization of styrene and acrylonitrile in liquid SO2 was conducted at 50°C. with αα′-azobiisobutyronitrile as an initiator. Relations between the over-all reaction rate and the initial concentration of each reactant were given. The composition of the copolymer in mole ratio was determined from the elementary analysis, and the result was compared with the theoretical values calculated from two different mechanisms. The agreement obtained by the calculation based on an assumption that the polymerization reaction proceeds via formation of a complex between sulfur dioxide and styrene was better than that obtained on a mechanism of direct polymerization of free sulfur dioxide. Copolymerisation von Styrol und Acrylnitril in flussigem Schwefeldioxyd wurde bei 50°C mit Azodiisobutyronitril als Initiator ausgefuhrt. Es werden Beziehungen zwischen der Bruttoreaktionsgeschwindigkeit und der Anfangskonzentration aller Reaktionsteilnehmer aufgestellt. Die grundmolare Zusammensetzung der Copolymeren wurde durch Elementaranalyse bestimmt und das Ergebnis mit den theoretischen Werten verglichen, die man unter der Voraussetzung zweier verschiedener Reaktionsmechanismen zu erwarten hat. Danach stimmt die Annahme, das die Polymerisationsreaktion durch die Bildung von Komplexen zwischen Schwefeldioxyd und Styrol zustandekommt, besser mit den experimentellen Ergebnissen uberein, als es bei der Annahme der direkten Polymerisation von freiem Schwefeldioxyd der Fall ist.

The radical copolymerization of sulfur dioxide and chloroprene (CP) in benzene was carried out, especially as a function of the total monomer concentration ([SO2] + [CP]). The composition of chloroprene polysulfones varies mainly with total monomer concentration and with polymerization temperature, but depends very slightly on feed composition. The microstructure of chloroprene units in chloroprene polysulfone was such that the trans-1,4 unit was predominantly over the cis-1,4 unit. Thus it would seem possible to rule out both radical copolymerization mechanisms, i.e., propagation of separate monomers as explained by the Lewis-Mayo equation, and propagation processes involving a monomer charge-transfer complex.

Tetraethyl ammonium bromide, tetramethyl ammonium bromide, ammonium bromide, tetraethyl ammonium chloride, and tetraethyl ammonium iodide were respectively added in the radical polymerization of acrylonitrile in liquid sulfur dioxide. The temperature of polymerization was 50°C. The result showed that the over-all rate of polymerization was retarded by the addition of these ammonium salts. The retarding effect was caused by the anions and not by the ammonium cations, and the contribution to the retardation by the ammonium salts were in the order of Cl− < Br− ≪ I−, especially in the case of tetraethyl ammonium iodide, the polymerization being completely inhibited. The lowering tendency in the degree of polymerization was also similar in the ammonium salts containing the sam halogenic anion. It was therefore concluded that the retarding effect of ammonium salt was due to the stabilizing action of the halogenic anion on the radical end of growing chains. It was also found that, as it was the case in the radical polymerization of acrylonitrile in liquid sulfur dioxide, no polysulfone but only polyacrylonitrile was obtained. There was no influence of ammonium salt on the course of the polymerization of acrylonitrile in liquid sulfur dioxide. Tetraathylammoniumbromid oder -jodid sowie Tetramethylammoniumbromid oder -jodid und ferner Ammoniumbromid wurden zur radikalischen Polymerisation von Acrylnitril in flussigem Schwefeldioxyd zugesetzt (Polymerisationstemperatur 50°C). Die Polymerisationsgeschwindigkeit wird durch Zusatz dieser Ammoniumsalze verzogert, und zwar durch die Anionen. Ihre Verzogerungswirkung nimmt von Cl− uber Br− zum J− zu; beim Tetraathylammoniumjodid ist die Polymerisation sogar vollstandig inhibiert. Die Verringerung der Polymerisationsgeschwindigkeit bei Zusatz der verschiedenen Ammoniumsalze mit demselben Halogenid ist praktisch gleich gros. Es wurde auch hier, wie bei der radikalischen Polymerisation von Acrylnitril in flussigem Schwefeldioxyd, keine Polysulfonbildung beobachtet; der Zusatz der Ammoniumsalze beeinflust die Polymerisation des Acrylnitrils in flussigem Schwefeldioxyd also nicht.

Acrylonitrile was polymerized in liquid sulfur dioxide at a temperature of 50°C., using azo-bis-isobutyronitrile as initiator. Elemental analyses of the polymer obtained showed that the product was homopolymer acrylonitrile irrespective of the conditions and the conversion. Radical polymerization of vinyl compounds in liquid sulfur dioxide was thought to give a polysulfone and the present result can be explained by considering a repulsion between sulfur dioxide and acrylonitrile. Polymerization generally proceeds in heterogeneous system and the overall rate of the polymerization (Rp) was found to be represented by the equation: The activation energy for the reaction was calculated as 22.4 Kcal/Mole. The decomposition rate constant of the initiator and its chain transfer constant to the acrylonitrile monomer in liquid sulfur dioxide were calculated. Acrylnitril wurde bei 50°C mit Azo-bis-isobutyronitril in flussigem Schwefeldioxyd polymerisiert. Nach der Elementaranalyse ist das erhaltene Polymere unabhangig von den Bedingungen und dem Umsatz ein Homopolymerisat des Acrylnitrils. Es war angenommen worden, das die radikalische Polymerisation von Vinylverbindungen in flussigem Schwefeldioxyd zur Bildung von Polysulfonen fuhren wurde, das dies im vorliegenden Fall nicht erfolgte, kann durch eine Abstosung von Schwefeldioxyd und Acrylnitril erklart werden. Die Polymerisation von Acrylnitril in flussigem Schwefeldioxyd erfolgt in einem heterogenen System und die Polymerisationsgeschwindigkeit Rp kann mit folgender Gleichung wiedergegeben werden: Die Aktivierungsenergie der Reaktion errechnet sich zu 22,4 kcal/Mol. Ferner wurden auch die Konstanten der Zersetzungsgeschwindigkeit des Initiators und der Kettenubertragung auf das Monomere im flussigen Schwefeldioxyd berechnet.

The optical spectra of the alkali metal salts of arylthiolate anions have been studied in the two aprotic solvents, tetrahydrofuran (THF) and dimethylformamide (DMF). In the former solvent the position of the absorption maxima depends on the size of the counter cations, even at low temperatures (−72 to −76 °C); nearly linear relationships were observed between the inverse of the alkali metal radius (rc) and the wave number of the transition (\ ildeνmax) for both room and low temperatures. The intercepts for the extrapolation of both lines for 1/rc→0 agree with the \ ildeνmax of the ion pairs observed in DMF at room temperature, and the absorption maxima for this solvent are independent of the size of the counter cations. Thus, the existence of contact ion pairs in THF over the temperature range investigated and that of the solvent-separated ion pairs in DMF at room temperature were revealed. In the latter solvent, however, a hypsochromic shift was observed on lowering the temperature. The substituent effe...