scholarly journals Synthesis and Characterization of Semicrystalline Polyimides Containing Bridged Linkages

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Min Chao
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
High Weight ◽  
Softening Temperature ◽  
Synthesis And Characterization ◽  
Excellent Thermal Stability

A series of polyimides (PI) containing bridged linkages were prepared successfully through a three-step technique. The results indicated that the glass transition temperature (Tg) of polyimides was affected by flexibility of polymer chain and the intermolecular interactions. ODPA-TPER-based polyimide possesses the lowest Tg, which was 214°C. All polyimides had semicrystalline characteristics, and ODPA-TPER-based PI exhibited the lowest melting temperature (Tm) at 316°C. The polyimides had high weight loss temperatures, which indicated that bridged linkages can reduce the softening temperature, meanwhile keeping excellent thermal stability.

Synthesis and characterization of extended poly(phenylquinoxalines) containing carbonyl, ether and sulphide linking groups

1995 ◽  
Vol 7 (4) ◽  
pp. 481-492 ◽  
Author(s):  
Rajendra K Singh ◽  
Rooma Mago Mehta ◽  
R G Bass
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Glass Transition ◽  
Transition Temperature ◽  
Primary Objective ◽  
Synthesis And Characterization ◽  
Glass Transition Temperatures ◽  
Hydrocarbon Solvents ◽  
As Solubility

A series of eight novel extended poly(phenylquinoxalines) (PPQs) containing carbonyl, ether and sulphide linking groups were prepared by polycondensation of 4,4'-bis(phenylglyoxalyl-4-phenoxy-4'-benzoyl)diphenyl sulphide, I-D, and 4,4'-bis(phenyl glyoxalyl-4-phenylthio-4'-benzoyl)diphenyl sulphide, 2-D, with four aromatic bis(o-diamines) in m-cresol. The primary objective of this study was to correlate the effect of these linkages on the various properties such as solubility, thermal stability and glass transition temperature of the PPQs. Polymerization of 1-D was carried out in an oil bath maintained at 195-200C whereas polymerization of 2-D was performed at ambient temperature. The polymers prepared were soluble in m-cresol. dimethylsulphoxide, N,N-dimethylacetamide, I-methyl-2-pyrrolidinone and chlorinated hydrocarbon solvents, and formed tough transparent, yellow fingernail-creasable films from chloroform solutions. The inherent viscosities ranged between 0.44 and 0.96 dl g' '. The glass transition temperatures were nearly identical for both systems and ranged from 217-231 'C for polymers prepared from l-D and from 215-233"C for polymers prepared from 2-D. The PPQs having carbonyl and stJlphide linking groups had higher thermal stability in comparison to PPQs having carbonyl, ether and sulphide linkages. The temperature of 10% weight loss for I-D ranged from 484-496 'C in air and 485-516"C in helium whereas those for 2-D ranged from 538-579 XC in air and 522-549 in helium.

Synthesis and properties of random polysulfone/polyethersulfone copolymers as high-performance polymers

2011 ◽  
Vol 31 (4) ◽  
Author(s):  
Yi-Nan Zhang ◽  
Shu-Ling Zhang ◽  
Yan-Hua Yang ◽  
Hong-Yi Qin ◽  
Dong Jiang
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Tensile Strength ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
High Performance ◽  
Excellent Thermal Stability ◽  
Elongation At Break ◽  
High Performance Polymers

Abstract A series of random polysulfone/polyethersulfone (PSF/PES) copolymers were synthesized by the polycondensation of 4,4′-isopropylidenediphenol, 4,4′-dihydroxyldiphenylsulfone, and 4,4′-dichlorodiphenylsulfone in the presence of potassium carbonate. The resulting copolymers displayed similar solubility with PSF and PES. The glass transition temperature and the 5% weight loss temperature of these copolymers varied in the range of 199°C–299°C and 467°C–498°C, respectively, which showed excellent thermal stability. Moreover, the elongation at break of these copolymers was much higher than that of PES, whereas the tensile strength was a little lower.

Synthesis and characterization of polyurethanes bearing carbosilane segments

RSC Advances ◽  
2016 ◽  
Vol 6 (97) ◽  
pp. 94803-94808
Author(s):  
Ayumu Karimata ◽  
Kozo Matsumoto ◽  
Takeshi Endo
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Synthesis And Characterization ◽  
And Storage ◽  
Lower Glass Transition Temperature

New polyurethanes bearing carbosilane segment (1a–c) were synthesized and found to exhibit lower glass transition temperature and storage moduli than corresponding reference polyurethanes 2a–c, while thermal stability was retained.

scholarly journals Design of an n-type low glass transition temperature radical polymer

2021 ◽  
Author(s):  
Teng Chi ◽  
Siddhartha Akkiraju ◽  
Zihao Liang ◽  
Ying Tan ◽  
Ho Joong Kim ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Synthesis And Characterization ◽  
Design Synthesis

We document the design, synthesis, and characterization of the first low glass transition temperature, n-type (i.e., preferentially-reduced) radical polymer.

scholarly journals Polarization and Piezoelectric Properties of a Nitrile Substituted Polyimide

1996 ◽  
Vol 459 ◽  
Author(s):  
Joycelyn Simpson ◽  
Zoubeida Ounaies ◽  
Catharine Fay
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Remanent Polarization ◽  
Piezoelectric Properties ◽  
Synthesis And Characterization

ABSTRACTThis research focuses on the synthesis and characterization of a piezoelectric (β-CN)-APB/ODPA polyimide. The remanent polarization and piezoelectric d31 and g33 coefficients are reported to assess the effect of synthesis variations. Each of the materials exhibits a level of piezoelectricity which increases with temperature. The remanent polarization is retained at temperatures close to the glass transition temperature of the polyimide.

Synthesis and characterization of new silicon-containing poly(arylene-1,3,4-oxadiazole)s

1995 ◽  
Vol 7 (4) ◽  
pp. 493-501 ◽  
Author(s):  
I Sava ◽  
B Schulz ◽  
S Zhu ◽  
M Bruma
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Synthesis And Characterization ◽  
Polycondensation Reaction ◽  
Cyclization Process ◽  
Film Forming ◽  
Temperature Solution ◽  
Solution Polycondensation

New silicon-containing aromatic polyhydrazides were synthesized by low-temperature solution polycondensation reaction of bis(p-chlorocarbonylphenyl)diphenylsilane with various aromatic dihydrazides, or of bis(p-carbohydrazidophenyl)diphenylsilane with diacid chlorides. The corresponding poly(arylene-1,3,4-oxadiazole)s wvere prepared by thermal cyclodehydration in the solid state. The cyclization process takes place at temperatures in the range of 250-300 IC. The resulting silicon-containing poly(arylene-1,3,4-oxadiazole)s are soluble in common organic solvents and have good film-forming abilities. They are stable up to 420-480 'C and their glass transition temperature is in the range of 262-278C.

scholarly journals Synthesis and characterization of methylammonium phosphates as crystalline approximants for anhydrous, low melting phosphate glasses

RSC Advances ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 1822-1830
Author(s):  
Martin Mangstl ◽  
Jan Konrad Wied ◽  
Johannes Weber ◽  
Christian Pritzel ◽  
Reinhard Trettin ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Phosphate Glass ◽  
Phosphate Glasses ◽  
Synthesis And Characterization ◽  
The Novel

The novel glass shows the lowest glass transition temperature known for binary phosphate glass systems without acidic protons.

scholarly journals Synthesis and Characterization of Poly(Acrylic Acid)/Organo-Modified Nanohydroxyapatite Nanocomposites: Thermal, Optical and Biocompatibility Properties

2018 ◽  
Vol 18 (3) ◽  
pp. 54-67 ◽  
Author(s):  
M. E. Diken ◽  
S. Doğan ◽  
Y. Turhan ◽  
M. Doğan
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Simulated Body Fluid ◽  
Acrylic Acid ◽  
Body Fluid ◽  
Synthesis And Characterization ◽  
Uv Absorbance ◽  
Poly Acrylic Acid

AbstractThe aim of this study was to investigate the structural, thermal, optical and biocompatibility properties of poly(acrylic acid)(PAA)/organo-modified nanohydroxyapatite (OM-nHAp) nanocomposites synthesized by solvent intercalation method. The characterization of PAA/OM-nHAp nanocomposites was made by different techniques. SEM and TEM results showed that OM-nHAp particles were dispersed in the nanoscale into PAA matrix and that they were uniformly distributed within film. Glass transition temperature of PAA increased with OM-nHAp content. Ultraviolet (UV) absorbance experiments showed that PAA had a higher UV transmission than its nanocomposites. The biocompatibility of nanocomposites was also examined in simulated body fluid.

Sign in / Sign up

Export Citation Format

Share Document