Communication

1997 ◽  
Vol 9 (4) ◽  
pp. 457-460
Author(s):  
K B Patel ◽  
K R Desai ◽  
H S Patelk
Keyword(s):  
Molecular Weight ◽  
Electrical Properties ◽  
Room Temperature ◽  
Average Molecular Weight ◽  
Conductometric Titration ◽  
Spectral Studies ◽  
Number Average Molecular Weight ◽  
Elemental Analyses

Four various poly(urethane-urea)s (PUUs) were prepared by polycondensation of 3-aminophenol with various diisocyanates. The resultant poly(urethane-urea)s were characterized by elemental analyses, IR spectral studies, number average molecular weight ( Mn) estimated by non-aqueous conductometric titration and thermogravimetry. The electrical properties of these polymers have also been measured at room temperature.

scholarly journals Synthesis and Characterization of Colored Polyureas

2004 ◽  
Vol 1 (1) ◽  
pp. 51-56 ◽  
Author(s):  
M. G. Patel ◽  
K. R. Desai ◽  
H. S. Patel
Keyword(s):  
Electrical Conductivity ◽  
Molecular Weight ◽  
Room Temperature ◽  
Average Molecular Weight ◽  
Conductometric Titration ◽  
Spectral Studies ◽  
Synthesis And Characterization ◽  
Disperse Dyes ◽  
Number Average Molecular Weight

Various disperse dyes based onm-phenylenediamine have been prepared. These dyes then polycondensation with 4,4'-Diphenyl methane diisocyanate. The resultant colored polyureas were characterized by N content, IR spectral studies, Number Average Molecular Weight (Mn) estimation by nonaqueous conductometric titration and thermogravimetry. All the polyureas were subjected to measure electrical conductivity at room temperature.

scholarly journals Synthesis, Characterization and Glass - Reinforced Composites of Thiourea - Formaldehyde - Phenol Resin

2004 ◽  
Vol 1 (5) ◽  
pp. 256-262 ◽  
Author(s):  
Kanuprasad Dahyalal Patel ◽  
Dhirubhai J. Desai ◽  
Manish M. Morekar ◽  
Yogesh Shrikant Tilak
Keyword(s):  
Molecular Weight ◽  
Differential Scanning Calorimetry ◽  
Average Molecular Weight ◽  
Conductometric Titration ◽  
Spectral Studies ◽  
Reinforced Composites ◽  
Number Average Molecular Weight ◽  
Scanning Calorimetry ◽  
Alcoholic Alkali ◽  
Glass Reinforced Composites

N,N'-Dimethylol thiourea-formaldehyde (DMTUF) resin having the methylol group (CH2OH) has been prepared and characterized. The condensation of DMTUF resin with Phenol (P) was carried out in the presence of alcoholic alkali catalyst at varying ratios of DMTUF: P, namely 1:1, 1:1.5 and 1:2. The resultant DMTUFP resin was characterized by elemental analysis, IR spectral studies, number average molecular weight (M¯n) estimated by non-aqueous conductometric titration, and thermo gravimetry. The curing study of DMTUFP resin with hexamethylene tetramine (HMTA) was monitored by differential scanning calorimetry (DSC) and kinetic parameters were evaluated. Glass-reinforced composites based on the DMTUFP-HMTA system have also been prepared and characterized.

Synthesis, Characterization and Glass-Reinforced Composites of Acetone–Formaldehyde–Phenol Resins

1997 ◽  
Vol 9 (2) ◽  
pp. 153-160 ◽  
Author(s):  
Hasmukh S Patel ◽  
Bharat C Dixit
Keyword(s):  
Molecular Weight ◽  
Differential Scanning Calorimetry ◽  
Average Molecular Weight ◽  
Conductometric Titration ◽  
Spectral Studies ◽  
Reinforced Composites ◽  
Number Average Molecular Weight ◽  
Scanning Calorimetry ◽  
Alcoholic Alkali ◽  
Glass Reinforced Composites

Acetone–formaldehyde (AF) resin having the methylol group (–CH2OH) has been prepared and characterized. The condensation of AF resin with phenol (P) was carried out in the presence of alcoholic alkali catalyst at varying ratios of AF:P, namely 1:1, 1:1.5 and 1:2. The resultant AFP resins were characterized by elemental analysis, IR spectral studies, number average molecular weight ( Mn) estimated by non-aqueous conductometric titration, and thermogravimetry. The curing study of AFP resins with hexamethylene tetramine (HMTA) was monitored by differential scanning calorimetry (DSC) and kinetic parameters were evaluated. Glass-reinforced composites based on the AFP–HMTA system have also been prepared and characterized.

Physicochemical study of complexation and ion-exchange properties of 2-hydroxy-4-ethoxypropiophenone—ethylene glycol polymer

1994 ◽  
Vol 6 (2) ◽  
pp. 123-132 ◽  
Author(s):  
Jayesh R Patel ◽  
Dipan H Sutaria ◽  
Magan N Patel
Keyword(s):  
Molecular Weight ◽  
Ion Exchange ◽  
Ethylene Glycol ◽  
Polyphosphoric Acid ◽  
Average Molecular Weight ◽  
Thermal Studies ◽  
Conductometric Titration ◽  
Number Average Molecular Weight ◽  
Elemental Analyses ◽  
Exchange Properties

Copolymers (HEPP-EG) were synthesized by the condensation of 2-hydroxy-4-ethoxypropiophenone with ethylene glycol in presence of polyphosphoric acid as a catalyst. The copolymers were characterized by elemental analyses, IR spectra, viscosity and thermal studies. The number-average molecular weight (Mn) was measured by non-aqueous conductometric titration. The copolymer HEPP-EG-6 was complexed with metal ions, Cu2+, Ni2+, Co2, Mn2+ and Zn2+ and characterized. Chelation ion-exchange properties have been studied by employing the batch equilibration method.

scholarly journals Synthesis, Characterization and Glass - Reinforced Composites of N,N'-Dimethylolthiourea – m-Aminophenol Resin

2005 ◽  
Vol 2 (2) ◽  
pp. 136-141
Author(s):  
K. D. Patel ◽  
M. M. Morekar ◽  
Y. S. Tilak
Keyword(s):  
Molecular Weight ◽  
Differential Scanning Calorimetry ◽  
Average Molecular Weight ◽  
Conductometric Titration ◽  
Spectral Studies ◽  
Reinforced Composites ◽  
Number Average Molecular Weight ◽  
Scanning Calorimetry ◽  
Alcoholic Alkali ◽  
Glass Reinforced Composites

N,N’-Dimethylolthiourea (DMTU) resin having the methylol group ( –CH2OH ) has been prepared and characterized. The condensation of DMTU resin with m-aminophenol was carried out in the presence of alcoholic alkali catalyst at varying ratios of DMTU: mAP, namely 1:1, 1:1.5 and 1:2. The resultant DMTUmAP resin was characterized by elemental analysis, IR spectral studies, number average molecular weight (M¯n) estimated by non-aqueous conductometric titration, and thermogravimetry. The curing study of DMTUmAP resin with hexamethylenetetramine (HMTA) was monitored by differential scanning calorimetry (DSC) and kinetic parameters were evaluated. Glass-reinforced composites based on the DMTUmAP-HMTA system have also been prepared and characterized.

Novel Bismaleimide–Epoxy Resin System: II

1996 ◽  
Vol 8 (2) ◽  
pp. 233-242
Author(s):  
Hasmukh S Patel ◽  
Sanket N Shah
Keyword(s):  
Epoxy Resin ◽  
Average Molecular Weight ◽  
Conductometric Titration ◽  
Diglycidyl Ether ◽  
Spectral Studies ◽  
Reinforced Composites ◽  
Resin System ◽  
Number Average Molecular Weight ◽  
Scanning Calorimetry ◽  
Epoxy Resin System

Novel diamines, namely N, N′-bis[1-(2-methyl-4-aminophenyl)ethanonyl]-1,4- benzenediamine (BMAED 1) and N, N′-bis[1-(4-methyl-3-animophenyl)ethanonyl]-1,4-benzenediamine (BMAED 2), have been prepared and reacted with various bismaleimides (BM) at a BM:diamine ratio of 1:2. The resulting oligoimides have been characterized by elemental analysis, IR spectral studies and the number average molecular weight ( Mn) estimated by non-aqueous conductometric titration and thermogravimetry. Some of the oligomides have been modified by addition (i.e. curing reaction) of epoxy resin, namely the diglycidyl ether of bisphenol-A, and studied by differential scanning calorimetry (DSC). The glass- and carbon-reinforced composites have also been prepared and characterized by their mechanical properties.

Preparation and characterization of novel soluble polyarylates derived from 9,9-bis[4-(4-chloroformylphenoxy)phenyl]xanthene with various bisphenols

2017 ◽  
Vol 30 (10) ◽  
pp. 1203-1209
Author(s):  
Yu-Ting Zhou ◽  
Shou-Ri Sheng ◽  
Chuan-Chao Tang ◽  
Cheng Song ◽  
Zhen-Zhong Huang ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Weight Loss ◽  
Room Temperature ◽  
Phase Transfer ◽  
Average Molecular Weight ◽  
Interfacial Polycondensation ◽  
Number Average Molecular Weight ◽  
Glass Transition Temperatures ◽  
Flexible Films

A series of new polyarylates bearing cardo xanthene groups were synthesized by phase-transfer-catalyzed interfacial polycondensation of 9,9-bis[4-(4-chloroformylphenoxy)phenyl]xanthene with various bisphenols containing the isopropylidene, hexafluoroisopropylidene, 1-phenylethylidene, diphenylmethane, cyclohexane, and xanthene structures. High-molecular-weight polyarylates with number-average molecular weight and polydispersity index in the range of 30,100–35,300 and 1.82–2.17, respectively, exhibited high glass transition temperatures ranged from 226°C to 261°C, and their 10% weight loss temperatures were in the range of 421–452°C with char yields above 45% at 700°C in nitrogen. All the polyarylates were amorphous and readily soluble in organic solvents such as dichloromethane, chloroform, tetrahydrofuran, meta-cresol, pyridine, N,N-dimethylformamide, N,N-dimethylacetamide, and 1-methyl-2-pyrrolidinone at room temperature and could be cast into tough, transparent, and flexible films with tensile strengths of 85.6–108.3 MPa, elongations at break of 2–3%, and tensile moduli of 7–9 GPa.

Synthesis and characterization of poly(coumarin-urethane)s

1994 ◽  
Vol 6 (3) ◽  
pp. 257-262
Author(s):  
D I Brahmbbatt ◽  
L Jayabalan ◽  
Harshad D Patel
Keyword(s):  
Molecular Weight ◽  
Elemental Analysis ◽  
Vapour Pressure ◽  
Condensation Reaction ◽  
Average Molecular Weight ◽  
Spectral Studies ◽  
Synthesis And Characterization ◽  
Molecular Weight Determination ◽  
Number Average Molecular Weight

Poly(coumarin-urethane)s (PCUs) were prepared by the condensation reaction of 3,3'-dihydroxy-6,6'-methylcnebiscoumarin (DHMBC) with various diisocyanates. All the poly(coumarin-urethane)s were characterized by elemental analysis, IR spectral studies, number average molecular weight determination (by vapour pressure osmometry), viscosity studies and thermogravimetry.

Chemistry and Properties of Imide Oligomers from Phenylethynyl-Containing Diamines

2000 ◽  
Vol 12 (1) ◽  
pp. 213-223 ◽  
Author(s):  
J G Smith ◽  
J W Connell
Keyword(s):  
Thin Films ◽  
Molecular Weight ◽  
Research Effort ◽  
Average Molecular Weight ◽  
Number Average Molecular Weight ◽  
Similar Composition ◽  
Imide Oligomers ◽  
Calculated Number

As an extension of work on pendent phenylethynyl-containing imide oligomers, three new diamines containing pendent phenylethynyl groups were prepared and characterized. These diamines were used to prepare pendent and pendent and terminal phenylethynyl imide oligomers via the amide acid route in N-methyl-2-pyrrolidinone at a calculated number average molecular weight of 5000 g mol−1. The pendent phenylethynyl groups were randomly distributed along the oligomer backbone and provided a means of controlling the distance between reactive sites. The imide oligomers were characterized and thermally cured, and the cured polymers evaluated as thin films and compared with materials of similar composition prepared from 3,5-diamino-4′-phenylethynylbenzophenone. This work was performed as part of a continuing research effort to develop structural resins for potential aeronautical applications.

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