摘要:

Methyl trioxane and dimethyl trioxane were synthesized by the cotrimerization of formaldehyde and acetaldehyde. The structures of these two compounds were confirmed by elemental analyses, IR spectra, mass spectra, and NMR spectra. The methyl trioxane was able to polymerize by boron trifluoride etherate, giving a polyoxymethylene, but the dimethyl trioxane was hardly polymerized.

ISSN:0022-233X    

DOI:10.1080/10601326708053994

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

To obtain ultraviolet stabilizing polymers, 2-hydroxy-4-acryloyloxybenzophenone was prepared from 2,4-dihydroxybenzophenone and copolymerized with styrene. Copolymers containing three different amounts of ultraviolet absorber were prepared. These copolymers, unstabilized pure polystyrene and a series of stabilized polystyrene, were exposed to ultraviolet, and the ultraviolet stability of these polymers was compared by the relative amount of infrared absorption around 1700 cm−1due to the carbonyl group. Ultraviolet stability of the copolymers is very similar to that of blend polymers and is higher than that of unstabilized pure polystyrene.

ISSN:0022-233X    

DOI:10.1080/10601326708053995

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

Radiation-induced polymerization in binary component systems of acrylonitrile-methacrylonitrile and acrylonitrile-vinyl acetate was studied at −196°C. A mixture of two-component homopolymers was obtained from the acrylonitrile-methacrylonitrile system, which forms a eutectic mixture. When the mixture of acrylonitrile with vinyl acetate is cooled quickly from room temperature, a glassy state can be obtained. It was found that the copolymerization is possible in the glassy state at −196°C, and the monomer reactivity ratios were determined asr1= 6.0 andr2= 0.2 (M1= acrylonitrile), which coincides with the reported values on the radical copolymerization at room temperature.

ISSN:0022-233X    

DOI:10.1080/10601326708053996

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

An alternating linear copolymer ofcis,trans-1,5-cyclodecadiene and sulfur dioxide has been prepared in quantitative yield. Transannular carbon-carbon bond formation gives four saturated carbon atoms between the sulfone groups. The polymer is resistant to alkali but degrades thermally above 150°C with random chain cleavage.

ISSN:0022-233X    

DOI:10.1080/10601326708053997

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

Polyester elastomers were prepared by block copolymerization of dimethyl terephthalate (DMT), butanediol (BDO), and polytetramethylene glycol (PTMG). Polyester from DMT and butanediol forms a high-melting hard segment in block copolyester to prevent undue chain slippage when fibers are stretched. High elongation was provided by soft segment which consisted of condensation product from DMT and PTMG.

ISSN:0022-233X    

DOI:10.1080/10601326708053998

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

Dicyanoacetylene has been homopolymerized and copolymerized with styrene by a free-radical initiator. The homopolymerization was difficult to effect, but the copolymerization proceeded very well, to essentially a quantitative yield. Proof of the existence of a true copolymer was obtained by means of solubility tests and infrared spectroscopy. In addition, the reactivity ratios were calculated by means of infrared spectroscopy and it was found that ther1andr2values for styrene and dicyanoacetylene were 1.40 and approximately zero, respectively.

ISSN:0022-233X    

DOI:10.1080/10601326708053999

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

The rates of formation of pyrolysis products, identified by gas-liquid chromatography, of copolymers of methyl methacrylate with purem- and with purep-divinylbenzene show that the products derived from the meta-disubstituted unit in the meta cross-linked copolymer appear more rapidly than do those from the para-disubstituted units. This confirms the similar observation with corresponding styrene copolymers. The data from the methacrylate copolymers provide a less complicated degradative pattern, since depolymerization is the principal degradative process. The analytical data are less complicated also. The basic assumption that the relative rates of appearance of the disubstituted fragments are related to the distribution of the divinyl derived units in the network is, therefore, strengthened.

ISSN:0022-233X    

DOI:10.1080/10601326708054000

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

Free-radical copolymerizations of styrene with α-methylstyrene and methyl methacrylate and of acrylonitrile with α-methylstyrene have been carried out in the approximate regions of the ceiling temperatures of α-methylstyrene and methyl methacrylate. A theoretical treatment of copolymerization emphasizing the thermodynamic reversibility of particular propagation reactions has been compared with a kinetic treatment of copolymerization which emphasizes penultimate unit effects on the same propagation reactions. The former is found to adequately describe experimental copolymer composition data over a wide range of temperatures and over the complete range of monomer feed composition.

ISSN:0022-233X    

DOI:10.1080/10601326708054001

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

The influence of reversal of propagation reactions on copolymer composition has been studied for three systems: (1) anionic copolymerization of vinyl mesitylene (M1) and α-methylstyrene (M2) in tetrahydrofuran (THF), (2) radical copolymerization of styrene (M1) and methyl methacrylate (M2) ino-dichlorobenzene (ODCB), and (3) cationic copolymerization of styrene (M1) and α-methylstyrene (M2) in methylene chloride and in bulk.14C-labeled M2was used in systems (1) and (3).

ISSN:0022-233X    

DOI:10.1080/10601326708054002

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

Reaction modes ofn-butylmagnesium bromide with α,β-unsaturated esters, ketones, and nitriles were investigated in ether under anionic polymerization conditions.n-Butane and conjugate addition products observed were with all the monomers examined, but carbonyl addition products were not detected except with the unsaturated esters. Product distribution depends mainly upon reaction temperature and the concentration of the Grignard reagent, not upon the concentration of the unsaturated compounds.n-Butyl-magnesium bromide etherate in toluene gave similar results.

ISSN:0022-233X    

DOI:10.1080/10601326708054003

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor