Evaluation the influence of cesium 137 source on some physical properties and molecular weight of poly vinyl acetate at room temperature

Abstract Metalation of diene polymers such as poly (butadiene) and poly(isoprene) with sec-butyllithium and tetramethylethylenediamine in cyclohexane at room temperature forms lithiated polydienes. Reaction of the polylithiodienes with styrene or α-methylstyrene forms graft copolymers. The extent of metalation is much greater than previously reported metalations with n-butyllithium and tetramethylethylenediamine. The grafting efficiencies, determined by acetone extraction and gel permeation chromatography, are greater than 95 per cent. Graft copolymers of poly (styrene) on EPDM rubbers may also be prepared using this technique. The physical properties of the graft copolymers are a function of molecular weight, graft site level, and composition. Products at specific compositions and graft levels are thermoplastic elastomers. Their properties are comparable to SBS rubbers, and offer as an advantage high melt flow. Graft copolymers of poly(styrene) on poly(ethylene) and poly(ethylene-co-butene-1) result from the hydrogenation of the butadiene moeities of graft copolymers of poly (styrene) on 1,4-poly(butadiene) and 1,2 and 1,4-butadiene copolymers, respectively. Complete hydrogenation results in graft copolymers of poly(vinylcyclohexane) on poly(ethylene) and on poly(ethylene-co-butene-1). In both of these cases thermoplastic elastomers result if the proper choice of composition and graft level is made.

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Modification of Asphalt by Block Polymers of Butadiene and Styrene

Rubber Chemistry and Technology ◽

10.5254/1.3535936 ◽

1982 ◽

Vol 55 (5) ◽

pp. 1389-1402 ◽

Cited By ~ 54

Author(s):

Gerard Kraus

Keyword(s):

Molecular Weight ◽

Low Temperature ◽

Physical Properties ◽

Room Temperature ◽

Softening Temperature ◽

Block Polymers ◽

Rich Phase ◽

Block Polymer ◽

Low Concentrations ◽

Low Temperature Flexibility

Abstract Elastomeric thermoplastic block polymers of butadiene and styrene are highly effective in converting asphalts into truly rubber-like materials. Additions of 10–14% of these polymers to asphalt result in lower penetration values, greatly reduced flow above room temperature, increases in softening temperature to values in excess of 100°C and superior low temperature flexibility. The blends are characterized by a unique morphology in which the block polymer, swollen with the lower molecular weight constituents of the asphalt, forms a continuous lacework in a bituminous phase enriched with asphaltenes. The polymer-rich phase consists, in turn, of two microphases derived from the block polymer domain structure. At low concentrations, where the swollen polymer forms discrete inclusions in the asphaltic continuum, effects on the physical properties of the asphalt are less pronounced but can still be significant. The multiphase morphology of these composites accounts satisfactorily for the most important features of their mechanical behavior.

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Improved Sol-Gel Materials for Efficient Solid State Dye Lasers

MRS Proceedings ◽

10.1557/proc-329-279 ◽

1993 ◽

Vol 329 ◽

Cited By ~ 3

Author(s):

Michael Canva ◽

Patrick Georges ◽

Jean-Fran^ois Perelgritz ◽

Alain Brun ◽

Fréddric Chaput ◽

...

Keyword(s):

Solid State ◽

Physical Properties ◽

Room Temperature ◽

Sol Gel ◽

Tunable Lasers ◽

Optical Quality ◽

Dye Lasers ◽

Laser Dyes ◽

Host Matrix ◽

Host Matrices

AbstractPhotoresistant laser dyes were trapped in silica based xerogel host matrices to obtain solid state tunable lasers. For this purpose very dense xerogel samples with improved chemical and physical properties were prepared at room temperature by the sol-gel technology. The as-prepared materials were polished to obtain optical quality surfaces and were used as new lasing media.Lasing action of such different dyes as rhodamine, perylene and pyrromethene doping dense sol-gel matrices was demonstrated. Efficiencies of 30 % or lifetimes of more than 100,000 shots were achieved with different new ≤dye dopant/host matrix≥ couples. Their different performances are reviewed and discussed.

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Degradation in a Methyl-phenyl Co-Polymeric Polysilane for LED Applications

MRS Proceedings ◽

10.1557/proc-769-h4.3 ◽

2003 ◽

Vol 769 ◽

Cited By ~ 2

Author(s):

Asha Sharma ◽

Deepak ◽

Monica Katiyar ◽

Satyendra Kumar ◽

V. Chandrasekhar ◽

...

Keyword(s):

Thin Films ◽

Molecular Weight ◽

Light Source ◽

Room Temperature ◽

Light Exposure ◽

Room Temperature Photoluminescence ◽

Pl Spectrum ◽

Pl Intensity ◽

Methyl Phenyl

AbstractThe optical degradation of polysilane copolymer has been studied in spin cast thin films and solutions using light source of 325 nm wavelength. The room temperature photoluminescence (PL) spectrum of these films show a sharp emission at 368 nm when excited with a source of 325 nm. However, the PL intensity deteriorates with time upon light exposure. Further the causes of this degradation have been examined by characterizing the material for its transmission behaviour and changes occurring in molecular weight as analysed by GPC data.

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HAYNES STELLITE ALLOY No. 98M2

Alloy Digest ◽

10.31399/asm.ad.co0022 ◽

1960 ◽

Vol 9 (7) ◽

Keyword(s):

Fracture Toughness ◽

Compressive Strength ◽

Physical Properties ◽

Room Temperature ◽

Base Alloy ◽

Heat Treating ◽

The Other ◽

Stellite Alloy ◽

Cobalt Base Alloy ◽

Cobalt Base

Abstract HAYNES STELLITE 98M2 Alloy is a cobalt-base alloy having higher compressive strength and higher hardness than all the other cobalt-base alloys at room temperature and in the red heat range. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive strength as well as fracture toughness. It also includes information on heat treating, machining, and joining. Filing Code: Co-22. Producer or source: Haynes Stellite Company.

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FANSTEEL 85 METAL

Alloy Digest ◽

10.31399/asm.ad.cb0007 ◽

1981 ◽

Vol 30 (6) ◽

Keyword(s):

High Temperature ◽

Physical Properties ◽

Creep Strength ◽

Room Temperature ◽

Elevated Temperatures ◽

Base Alloy ◽

Heat Treating ◽

Good Combination ◽

Bend Strength ◽

Temperature Performance

Abstract FANSTEEL 85 METAL is a columbium-base alloy characterized by good fabricability at room temperature, good weldability and a good combination of creep strength and oxidation resistance at elevated temperatures. Its applications include missile and rocket components and many other high-temperature parts. This datasheet provides information on composition, physical properties, microstructure, hardness, elasticity, tensile properties, and bend strength as well as creep. It also includes information on low and high temperature performance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Cb-7. Producer or source: Fansteel Metallurgical Corporation. Originally published December 1963, revised June 1981.

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MAGNESIUM ZK61A

Alloy Digest ◽

10.31399/asm.ad.mg0067 ◽

1969 ◽

Vol 18 (10) ◽

Keyword(s):

Corrosion Resistance ◽

Physical Properties ◽

Tensile Properties ◽

Room Temperature ◽

Heat Treating ◽

Strength Properties ◽

Casting Alloy ◽

Chemical Company ◽

Casting Alloys ◽

Magnesium Casting

Abstract Magnesium ZK61A is a heat treatable sand casting alloy offering higher strength properties for room-temperature applications than other magnesium casting alloys. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Mg-67. Producer or source: The Dow Chemical Company.

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MAGNESIUM AZ31B

Alloy Digest ◽

10.31399/asm.ad.mg0053 ◽

1962 ◽

Vol 11 (9) ◽

Keyword(s):

High Temperature ◽

Magnesium Alloy ◽

Physical Properties ◽

Room Temperature ◽

Heat Treating ◽

General Purpose ◽

Bearing Strength ◽

Temperature Performance ◽

Wrought Magnesium Alloy ◽

Metal Products

Abstract Magnesium AZ31B is a general purpose wrought magnesium alloy for room temperature service. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive, shear, and bearing strength as well as creep. It also includes information on low and high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Mg-53. Producer or source: The Dow Metal Products Company.

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DILLIDUR 450V

Alloy Digest ◽

10.31399/asm.ad.sa0638 ◽

2011 ◽

Vol 60 (12) ◽

Keyword(s):

Fracture Toughness ◽

Wear Resistance ◽

Physical Properties ◽

Tensile Properties ◽

Room Temperature ◽

Surface Hardness ◽

Heat Treating ◽

Hot Working ◽

Resistant Steel ◽

Bend Strength

Abstract Dillidur 450V is a water hardened wear-resistant steel with surface hardness at room temperature of 420-480 HB. The steel is easy to weld and bend. Hot working is not recommended. This datasheet provides information on composition, physical properties, hardness, tensile properties, and bend strength as well as fracture toughness. It also includes information on wear resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-638. Producer or source: Dillinger Hütte GTS.

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