New Developments in Soluble Thermoplastic High Glass Transition Temperature Polyimides

1992 ◽  
Vol 264 ◽  
Author(s):  
M. E. Rogers ◽  
T. M. Moy ◽  
Y. J. Kim ◽  
J. E. McGrath
Keyword(s):  
Glass Transition ◽  
High Temperature ◽  
Transition Temperatures ◽  
New Developments ◽  
Glass Transition Temperatures ◽  
Transparent Films ◽  
Very High ◽  
End Group ◽  
Temperature Applications

AbstractUtilizing solution imidization, molecular weight and end group control techniques, soluble, fully cyclized polyimides with very high glass transition temperatures have been developed to meet high temperature applications. Mechanistic aspects are investigated for solution imidization by both the polyamic acid route and by the ester-acid route. Polyimides based on pyromellitic dianhydride and a 3F diamine exhibit glass transition temperatures of 420 °C. These polyimides are soluble in polar aprotic solvents and form tough, transparent films which demonstrate mechanical integrity and thermooxidative stability at 700 °F. Various processing routes are explored to demonstrate the viability of these materials in high temperature applications. Details of the synthesis and characterization of these materials will be provided.

scholarly journals Studies of Formation Mechanism, Structure, and Properties of Network Copolymers Obtained by Cocuring of Rolivsan Thermosetting Resins with Aromatic Diamines

2019 ◽  
Vol 2019 ◽  
pp. 1-15
Author(s):  
B. A. Zaitsev ◽  
L. G. Kleptsova ◽  
I. D. Shvabskaya
Keyword(s):  
Glass Transition ◽  
High Temperature ◽  
Thermal Analyses ◽  
Polymer Network ◽  
Three Dimensional ◽  
Transition Temperatures ◽  
Structure And Properties ◽  
Aromatic Diamines ◽  
Thermosetting Resins ◽  
Glass Transition Temperatures

Rolivsan thermosetting resins (ROLs) demonstrate high glass-transition temperatures and excellent processability. In our work, high-temperature properties of ROLs were significantly improved using a novel technique for structural and chemical modification of microheterogeneous network polymers. This technique involves, among other procedures, cocuring of rolivsan resins with aromatic diamines (ADA). The most noticeable increase in storage moduli and glass transition temperatures (Tg) of these copolymers was achieved when ROLs were modified with 10-15 wt.% of ADA and the resulting blends were subjected to thermal treatment in air in the temperature range 180 to 320°C for several hours. FTIR, 13С NMR spectroscopy, and dynamic mechanical and thermal analyses were used for studying the structure and properties of the obtained products. It was demonstrated that the mechanism of formation of ROL-ADA copolymers includes the following high-temperature reactions: (i) three-dimensional radical copolymerization of unsaturated ROL components and (ii) cleavage of heat-sensitive methacrylate crosslinking units inside the polymer network. The second process is accompanied by formation of pending units of methacrylic acid and methacrylic anhydride, which participate in condensation reactions with ADA.

Synthesis of novel organic-soluble high-temperature aromatic polymers

1995 ◽  
Vol 7 (3) ◽  
pp. 337-345 ◽  
Author(s):  
Yoshio Imai
Keyword(s):  
Glass Transition ◽  
High Temperature ◽  
Main Chain ◽  
Phenyl Group ◽  
Current Work ◽  
Transition Temperatures ◽  
Polymer Backbone ◽  
Glass Transition Temperatures ◽  
Aromatic Polyamides ◽  
Polymer Main Chain

This paper reviews our current work on the synthesis of new organic-soluble aromatic polyamides and polyimides having high glass transition temperatures above 300 °C. Our strategy to achieve this goal is to introduce a bulky pendant phenyl group along the polymer backbone and to incorporate a crank and twisted non-coplanar structure into the polymer main chain.

scholarly journals Synthesis and characterization of semiaromatic polyamides comprising benzofurobenzofuran repeating units

2017 ◽  
Vol 8 (14) ◽  
pp. 2197-2209 ◽  
Author(s):  
Julien Cretenoud ◽  
Bilal Özen ◽  
Thomas Schmaltz ◽  
Daniel Görl ◽  
Alberto Fabrizio ◽  
...  
Keyword(s):  
Glass Transition ◽  
Synthesis And Characterization ◽  
Transition Temperatures ◽  
Glass Transition Temperatures

Extended π-conjugated segments such as benzofurobenzofuran can be included into polyamides with high glass transition temperatures.

Naphthalene-based poly(aryl ether)s. II. Synthesis and characterization of poly(ether ketone)s containing two 1,4-naphthylene moieties in the repeat unit

1997 ◽  
Vol 75 (10) ◽  
pp. 1346-1353 ◽  
Author(s):  
Zhi Yuan Wang ◽  
Peter W. Broughton
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Repeat Unit ◽  
Synthesis And Characterization ◽  
Transition Temperatures ◽  
Aryl Ether ◽  
Glass Transition Temperatures ◽  
Phenyl Sulfone ◽  
Ether Ketone

Two new monomers, 4-chloro-1-(4′-fluoro-1-naphthoyl)naphthalene and 1,4-bis(4′-fluoro-1′-naphthoyl)benzene, have been synthesized and polymerized with four different bisphenols to give two series of the naphthalene-based poly(ether ketone)s that are analogous to commercial PEEK and PEEKK. The effect of the introduction of one or two 1,4-naphthylene moieties, in the backbone of the repeat unit, on the glass transition temperatures has been studied. The glass transition temperatures usually increased by 20–45 °C upon replacing one 1,4-phenylene with one 1,4-naphthylene moiety. All new poly (ether ketone)s prepared in tetramethylene sulfone were amorphous, with the glass transition temperatures in a range of 212–273 °C. The polymer produced from 1,4-bis(4′-fluoro-1′-naphthoyl)benzene and 1,4-hydroquinone in phenyl sulfone as a solvent at 300 °C showed semicrystalline properties with a melting temperature of 310 °C. Keywords: naphthalene, poly(ether ketone)s, synthesis, characterization, glass transition temperature.

scholarly journals Phosphine Oxide Containing Poly(pyridinium salt)s as Fire Retardant Materials

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1141 ◽  
Author(s):  
Maksudul M. Alam ◽  
Bidyut Biswas ◽  
Alexi K. Nedeltchev ◽  
Haesook Han ◽  
Asanga D. Ranasinghe ◽  
...  
Keyword(s):  
Glass Transition ◽  
High Temperature ◽  
Phosphine Oxide ◽  
Printed Circuit Boards ◽  
Fire Retardant ◽  
High Yield ◽  
Transition Temperatures ◽  
Ionic Polymers ◽  
Glass Transition Temperatures ◽  
13C Nuclear Magnetic Resonance

Six new rugged, high-temperature tolerant phosphine oxide-containing poly(4,4′-(p-phenylene)-bis(2,6-diphenylpyridinium)) polymers P-1, P-2, P-3, P-4, P-5, and P-6 are synthesized, characterized, and evaluated. Synthesis results in high yield and purity, as confirmed by elemental, proton (1H), and carbon 13 (13C) nuclear magnetic resonance (NMR) spectra analyses. High glass transition temperatures (Tg > 230 °C) and high char yields (>50% at 700 °C) are determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. These new ionic polymers exhibit excellent processability, thin-film forming, high-temperature resistance, fire-resistance and retardation, coating, adhesion, mechanical and tensile strength, and n-type (electron transport) properties. The incorporation of phosphine oxide and bis(phenylpyridinium) moieties in the polymer backbones leads to high glass transition temperatures and excellent fire retardant properties, as determined by microcalorimetry measurements. The use of organic counterions allows these ionic polymers to be easily processable from several common organic solvents. A large variety of these polymers can be synthesized by utilizing structural variants of the bispyrylium salt, phosphine oxide containing diamine, and the counterion in a combinatorial fashion. These results make them very attractive for a number of applications, including as coating and structural component materials for automobiles, aircrafts, power and propulsion systems, firefighter garments, printed circuit boards, cabinets and housings for electronic and electrical components, construction materials, mattresses, carpets, upholstery and furniture, and paper-thin coatings for protecting important paper documents.

Synthesis and characterization of novel cyanofunctionalized poly(aryl ether ketone)s

e-Polymers ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Yunhe Zhang ◽  
Dianfu Ren ◽  
Shaowei Guan ◽  
Ying Na ◽  
Guibin Wang ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperatures ◽  
Aryl Ether ◽  
Excellent Thermal Stability ◽  
Glass Transition Temperatures ◽  
Young’S Moduli ◽  
Flexible Films ◽  
Aryl Ether Ketone ◽  
Ether Ketone

AbstractA series of cyanophenyl-substituted poly(aryl ether ketone)s (PAEKs) have been successfully synthesized from two new bisphenol monomers, (3,4- dicyano) phenylhydroquinone and (4-cyano) phenylhydroquinone respectively, and the thermal behaviour and the solubility have been characterized. These polymers exhibited high glass transition temperatures and excellent thermal stability. The glass transition temperatures ranged from 173 to 217 oC, and 5% weight-loss temperatures were above 470 oC. The solubilities of these polymers have been remarkably improved in common organic solvents over PEEK and PEN. Some polymers formed transparent, strong, and flexible films, with tensile strength of 106.5-125.2 MPa, Young’s moduli of 2.68-3.20 GPa, and elongations at break of 9- 16 %.

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