摘要:

AbstractA commercial differential scanning calorimeter has been used to determine thermal and kinetic data of some typical polymerization initiators. Since the rate of heat change due to decomposition is directly related to the rate of decomposition at a given temperature, suitable analysis of the differential thermal curve can yield the Arrhenius parameters of a reaction from a single run. In order to test the method, the well‐established first‐order decomposition of azobisisobutyronitrile was determined in di‐n‐butyl phthalate as solvent. Reproducible results were obtained which accorded with published data by orthodox determinations. The rates of thermal decomposition in solution of benzoyl peroxide and diisopropyl peroxydicarbonate were also determined. The method provides a rapid means for the direct determination of fast rates not possible with orthodox analytical determi

ISSN:0021-8995    

DOI:10.1002/app.1967.070110901

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA relatively simple and inexpensive instrument giving good accuracy and easy operation has been developed for the measurement of volume change in monomer polymerizations. The instrument is based on a previously described capillary dilatometer intended for automatic operation.

ISSN:0021-8995    

DOI:10.1002/app.1967.070110902

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe bulk polymerization of 2‐allylphenylacrylic ester and of 2‐allylphenylmethacrylic ester at 60–80°C. was studied. It was observed that under these conditions azobisisobutyronitrile, lauroyl peroxide, and benzoyl peroxide have satisfactory activity as initiators. The influence of atmospheric oxygen on AOAF and MOAF polymerization was proved. The peculiarities of AOAF and MOAF polymerization (low molecular weight of the soluble polymers which are formed, the absence of gel effect, relatively low critical conversions) may be explained on the basis of chain transfer reactions by the allylic

ISSN:0021-8995    

DOI:10.1002/app.1967.070110903

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe thermal degradation in oxygen of fifteen polymers containing aromatic rings in the chain has been studied by a weight loss method. The relative thermal stabilities of the different polymers have been determined and, where possible, the overall activation energy for breakdown. The results have been compared with those for samples of the same polymers degraded in vacuum. The most thermally stable of the polymers examined under oxidizing conditions was poly(2,6‐dichlorophenylene oxide), with a stability comparable with that of a copolymer of tetrafluoroethylene and hexafluoropropylen

ISSN:0021-8995    

DOI:10.1002/app.1967.070110904

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractAcrylamide, acrylic acid, and acrylonitrile have been polymerizedin situwithin wool fibers and the water‐absorption properties of the resultant wool–polymer systems compared with those of wool and the polymers measured separately. At high humidities, polyacrylamide and, to a lesser extent, poly(acrylic acid) caused increased water uptakes when expressed as a function of the original weight of wool, due to the hydrophilic nature of these polymers. This increase was less than that expected from the water contents of the wool and polymers measured as separate entities. Chain entanglements in the polymer–keratin network may be responsible for some reduction of water content. The presence of polyacrylonitrile in wool reduced the water content at high humidities to less than that of wool alone, indicating that “volume exclusion” of water by the polymers is also a contributing factor. At low humidities, the water content of the wool–polyacrylamide system is equivalent to the sum of the water contents of wool and polymer taken separately; in the case of poly(acrylic acid) the water content is less than that of wool and polymer considered separately, and this is attributed to ionic bonding. For wool containing polyacrylonitrile there is a reduction in water content at low humidities, indicating interaction between the polymer and polar sorption sites

ISSN:0021-8995    

DOI:10.1002/app.1967.070110905

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA simple theory is developed which correlates the Izod impact strength of polymers with (G′100‐G′300)2/G′100, whereG′100andG′300are dynamic shear moduli at 100°K. and 300°K., respectively. The theory assumes the Maxwell element for the material and the fracture time smaller than the relaxation time. The theory is verified by experimental data for numerous polymers. Another approach which correlates the impact strength with the integrated loss factor from 0 to 300°K. is als

ISSN:0021-8995    

DOI:10.1002/app.1967.070110906

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractOil‐bearing formations often consist of loose sandy material. In the production of oil from these formations sand tends to be carried to the well bore along with the oil. The flow of sand can be prevented by consolidating or cementing together the sand particles of the formation around the well bore. The cementing has to be accomplished in such a manner that fluid flow channels between particles remain open. This paper describes a new three‐step process that was developed to consolidate oil well sand. The steps in the process involve injection of: (1) resin, (2) inert fluid, and (3) inert fluid containing a catalyst. In the first step of the process, resin in injected into the formation where it fully saturates the interstices between sand grains. Permeability is established in the second step by displacement of the excess resin from the interstices, thereby leaving a thin film of resin on the sand grains. In the third step, polymerization is activated by migration of catalyst from the inert fluid into the thin resin film on the sand. The process has the advantage that resin is placed and permeability is established before the resin is catalyzed. This avoids premature polymerization of the resin which might cause plugging of the formation or the tubing string used to inject resin. Desirable characteristics of a resin for the three‐step process are: (1) viscosity of 25–200 cp. at well bore temperature; (2) stability for several days at well bore temperature; (3) high adhesion to sand in the presence of an inert flushing fluid; (4) polymerization by less than 10% catalyst; (5) the polymerized resin binds sand together with a strong bond that is not affected by well fluids. Five different resin types have been tested for use in the three‐step sand consolidation process. These are: (1) epoxy–anhydride cured with a tertiary amine; (2) epoxy–epoxy diluent cured with a primary–tertiary amine mixture; (3) furan; (4) unsaturated polyester–vinylpyrrolidone; (5) unsaturated polyester–styrene. The two epoxy resins give strong, permeable consolidated sand which is resistant to well fluids such as brine and crude oil. The furan resin gives a weak consolidation. The unsaturated polyester–vinylpyrrolidone gives good strength and oil resistance but is sensitive to brine. The unsaturated polyester–styrene is difficult to apply. Many oil wells have been successfully treated in the Gulf Coast area and in California with the two epoxy resins. Almost all of these wells are producing free of sand, and, to date, more than five million barrels of oil have been pr

ISSN:0021-8995    

DOI:10.1002/app.1967.070110907

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractIn the reaction of cotton cellulose fiber with propionyl chloride in pyridine–DMF medium, the degree of substitution based on weight gain was much higher than that based on saponification. Gas–liquid chromatograms of the pyrolysis products of the samples showed an extra peak. This was identified as 3‐pentanone, which arises from the pyrolysis of α‐propionylpropionic acid, a substance which was proposed by Malm and co‐workers as a possible side product. This conclusion was further confirmed by the infrared and NMR spectra of the liquid, collected fractionally on pyrolysis of the sample. Quantitative GLC showed that one òut of every four hydroxyl groups is substituted with an α‐propionylpropionyl moiety, the rest with propionyl groups. A possible mechanism for the side reaction has

ISSN:0021-8995    

DOI:10.1002/app.1967.070110908

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe reactions between cotton cellulose and a mixture of triethanolamine and epichlorohydrin in the presence of aqueous NaOH have been studied. It has been shown that cotton fabric pretreated with aqueous base and then reacted with a 3:1 mole ratio of epichlorohydrin to triethanolamine forms a strong base anion exchanger. Resultant properties differed from those of the product made by the conventional method of preparing ECTEOLA cellulose, a commercial product of the same reactants. Titration curves of the strong base cellulose exchangers were similar to that obtained with the product of the reaction between cotton and trimethylglycidylammonium chloride. Substitution of triethylamine for the triethanolamine also resulted in a quaternary base cellulose anion exchanger. A cyclic diquaternary salt, [2,5‐p‐dioxanylenebismethylene] bis[tris(2‐hydroxyethyl)ammonium chloride], has been isolated from the triethanolamine–epichlorohydrin mixture and a mechanism of the reaction has been p

ISSN:0021-8995    

DOI:10.1002/app.1967.070110909

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA polypropylene film was stretched at 100–160°C., quenched to room temperature, and then restretched at the same temperature perpendicularly to the first stretching. The reorientation behavior was investigated by using optical and x‐ray methods. During the restretching the monoaxial orientation caused by the stretching is converted into a new monoaxial orientation through a balanced state, wherenpp=nps

ISSN:0021-8995    

DOI:10.1002/app.1967.070110910

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY