Molecular modelling and structure studies of LARC-CPI semicrystalline polyimide

Brillhart, M.; Cheng, Yao-Yi; Nagarkar, Pradnya; Cebe, Peggy

doi:10.1016/s0032-3861(96)00817-8

Cited by 11 publications

(9 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For many years now, much effort has been dedicated toward studying the relationships between the choice of the basic monomers and the resulting properties of the synthesized homopolyimides or copolyimides. − Experimental characterizations include density and solubility determinations as well as thermal, mechanical and permeation analyses. Polyimides have also been studied using UV/vis spectrophotometry, wide-angle X-ray diffraction, , or even positron annihilation. , Within this context, it is interesting to add molecular dynamics (MD) simulations, which are able to provide a dynamic model of the polyimide under study at the molecular level. This information can be used either to complement and interpret experimental evidence or to predict the properties of new polyimide structures prior to their synthesis…”

Section: Introductionmentioning

confidence: 99%

“…In both cases, a large number of structural properties such as radial distribution functions or ring correlation functions, torsion angle distributions, characteristic ratio, elastic moduli or yield strains could be obtained from the models. − A similar attempt was carried out on perylene-containing polyimides in order to characterize the degree of intra- and intermolecular nematic order . Other applications of MD simulations to these systems include the transport of small gas molecules in polyimide matrixes − as well as the alignment of liquid crystal molecules on polyimide layers. − MD has also been used as a tool to complement scanning tunneling microscopy images of polyimide Langmuir−Blodgett films and X-ray diffraction studies, , as well as modeling the poling process in piezoelectric polyimides …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Chemical Influence of the Dianhydride and the Diamine Structure on a Series of Copolyimides Studied by Molecular Dynamics Simulations

et al. 2002

View full text Add to dashboard Cite

Molecular dynamics (MD) simulations are undertaken on a series of five copolyimides based on two different dianhydrides: the flexible 4,4′-oxydiphthalic dianhydride (ODPA) and the rigid bulky bicyclo(2.2.2)-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BCDA). The diamines are respectively 4,4′oxydi(phenylamine) (ODA), 2-trifluoride-4,4′-oxydi(phenylamine) (CF 3ODA) and 2-methoxy-4,4′-oxydi-(phenylamine) (MeOODA). These are potential candidates for gas separation membranes, and the effects of increasing BCDA content in ODPA/BCDA copolyimides as well as adding trifluoromethyl or methoxy substituents on the ODA are studied at the molecular level. Amorphous long-chain models are built using a hybrid pivot Monte Carlo/MD sampling preparation procedure. The reproducibility of this approach is tested on a series of eight independently prepared systems. Densities, cohesive energies, Hildebrand parameters, conformational characteristics, intermolecular structures, and the available void spaces are analyzed for each system under study. Both the BCDA moiety and the trifluoromethyl substituent on the diamine are found to have similar consequences on the properties of the copolyimide by decreasing chain cohesion and increasing the available void space. This is related to the steric effect of the BCDA dianhydride, while the trifluoromethyl combines both steric and electronic repulsion. The steric effect of the methoxy substituent on the diamine is not strong enough to significantly differ from the unsubstituted system.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Chemical Influence of the Dianhydride and the Diamine Structure on a Series of Copolyimides Studied by Molecular Dynamics Simulations

et al. 2002

View full text Add to dashboard Cite

show abstract

“…Although the oriented film had a tensile modulus in the stretch direction over twice as high as that of an unstretched film, its density (1.3950 g/cm 3 ) was only 1.1% higher. Given that the crystal density could be expected to be 13% higher than that of the completely amorphous polymer (28), and assuming that there are no unwetted voids, 8% crystallinity would be inferred for this specimen.…”

Section: Tda and Crystallization Of Poly(keto-ether-imides)mentioning

confidence: 99%

Uniaxial stretching of poly(keto‐ether‐imide) films

Hinkley

Dezern

Feuz

et al. 2004

Polymer Engineering & Sci

View full text Add to dashboard Cite

Narrow strips of various fully imidized polyimide films were stretched under constant load either isothermally or during a temperature ramp. The effects of process variables (load and temperature) on modulus, failure strain, and tensile strength of the stretched films were characterized and room temperature moduli of up to 16 GPa were documented. Several materials that undergo strain-induced crystallization were identified as candidates for further property optimization. Polym. Eng. Sci. 44:1360 -1367, 2004

show abstract

“…Hence, development of semicrystalline polyimides has attracted considerable attention for these years [6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22]. The most well-known semicrystalline polyimides include LaRC-CPI developed by NASA [23,24,25,26,27,28], New-TPI developed by Mitsui Toatsu Chemicals [29,30,31,32], R-BAPB type polyimides developed by the Russian Academy of Sciences [33,34,35,36], and some other semicrystalline polyimides developed by the University of Akron [37,38,39,40] and Virginia Polytechnic Institute [41,42,43,44,45]. Although these polyimides exhibit crystallinity, most of them can only crystallize in the presence of solvent and cannot recrystallize once taken to the melt [41].…”

Section: Introductionmentioning

confidence: 99%

Melt-Processable Semicrystalline Polyimides Based on 1,4-Bis(3,4-dicarboxyphenoxy)benzene Dianhydride (HQDPA): Synthesis, Crystallization, and Melting Behavior

et al. 2017

View full text Add to dashboard Cite

Abstract:It is a great challenge to develop semicrystalline polyimides exhibited significant recrystallization ability and fast crystallization kinetics from the melt. A series of semicrystalline polyimides based on 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride (HQDPA) and different diamines, including 1,3-bis(4-aminophenoxy)benzene (TPER), 1,4-bis(4-aminophenoxy)benzene (TPEQ), 4,4 -oxydianiline (4,4 -ODA) and 4,4 -bis(4-aminophenoxy)biphenyl (BAPB), end capped with phthalic anhydride were synthesized. Crystallization and melting behaviors were investigated by differential scanning calorimetry (DSC). The polyimide derived from HQDPA/TPER (PI-1) exhibited a glass transition temperature (T g ) at 190 • C and double melting temperatures (T m s) at 331 • C and 350 • C, and the polyimide derived from HQDPA/TPEQ (PI-2) displayed a T g at 214 • C and a T m at 388 • C. PI-1 and PI-2 showed significant recrystallization ability from melt and high crystallization rate by isothermal crystallization kinetics study, while polyimides based on 4,4 -ODA and BAPB lost crystallizability once taken to the melt. These polyimides also exhibited excellent thermo-oxidative stability with 5% weight loss temperature higher than 500 • C and good mechanical properties with tensile moduli of 2.0-3.3 GPa, tensile strengths of 85-105 MPa and elongations at break of 5-18%. PI-1 also possessed outstanding melt flowability with less than 300 Pa·s around 370 • C by rheological measurements.

show abstract

Molecular modelling and structure studies of LARC-CPI semicrystalline polyimide

Cited by 11 publications

References 21 publications

Chemical Influence of the Dianhydride and the Diamine Structure on a Series of Copolyimides Studied by Molecular Dynamics Simulations

Chemical Influence of the Dianhydride and the Diamine Structure on a Series of Copolyimides Studied by Molecular Dynamics Simulations

Uniaxial stretching of poly(keto‐ether‐imide) films

Melt-Processable Semicrystalline Polyimides Based on 1,4-Bis(3,4-dicarboxyphenoxy)benzene Dianhydride (HQDPA): Synthesis, Crystallization, and Melting Behavior

Contact Info

Product

Resources

About