Journal ArticleDOI
End-functionalized thermoplastic-toughened phthalonitrile composites: influence on cure reaction and mechanical and thermal properties
TLDR
In this paper, the feasibility of toughening novolac-phthalonitrile (NPN) resins using chemically modified poly(ether ether ketone) (PEEK).Abstract:
Phthalonitrile polymers are known for their high thermal stability and good mechanical properties. However, their brittle nature limits their application as structural composites in many critical areas. The present study investigates the feasibility of toughening novolac–phthalonitrile (NPN) resin using chemically modified poly(ether ether ketone) (PEEK). A telechelic PEEK bearing a phthalonitrile end group (PEEKPN) was synthesized via nucleophilic substitution of nitrophthalonitrile with the corresponding phenol–telechelic poly(ether ether ketone) (PEEKOH). Different compositions of NPN and PEEKOH–PEEKPN blends with curing agent, i.e. diaminodiphenylsulfone, were investigated for their cure behaviour and mechanical properties of their carbon fabric composites. In NPN–PEEKOH blends, crosslinking of the phthalonitrile groups was facilitated by phenol-mediated reactions resulting in the reduction of cure temperatures by around 130 °C with substantial improvement in thermal stability. Blending the resin with the thermoplastic enhanced the mechanical properties of the composites. The apparent flexural strength and impact strength of carbon fabric-reinforced composites were improved by more than 200 and 150%, respectively, on incorporation of 20 wt% PEEKOH in the NPN matrix. However, higher concentration of PEEKOH had a detrimental effect on the properties. Substitution of phenol end groups by phthalonitrile moieties led to integration of the PEEK moieties with the NPN matrix. However, it was not as conducive as PEEKOH for improving the matrix properties. The better performance of PEEKOH is attributed to the formation of polar heterocyclic groups like isoindoline by way of the phenol–nitrile reaction. © 2014 Society of Chemical Industryread more
Citations
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Journal ArticleDOI
Influence of molecular weight on thermal and mechanical properties of bisphenol A-based phthalonitrile resins
Journal ArticleDOI
Synthesis and characterization of low temperature curable phthalonitrile containing propargyl- novolacs through click-chemistry approach
Journal ArticleDOI
Fast-Processable Non-Flammable Phthalonitrile-Modified Novolac/Carbon and Glass Fiber Composites
Daria Poliakova,Oleg Konstantinovic Morozov,Ya.V. Lipatov,A. V. Babkin,Alexey V. Kepman,V. V. Avdeev,Boris Bulgakov +6 more
TL;DR: In this paper , a novolac oligomer with hydroxyl groups fully substituted by phthalonitrile moieties was synthesized with a quantitative yield, and the product was characterized by 1H NMR and FT-IR.
Journal ArticleDOI
Heat-resistant polymer composite materials based on heterocyclic matrices
Journal ArticleDOI
Curing of diphthalonitrile resin
TL;DR: In this article, the authors studied the curing of diphthalonitrile resins by IR spectroscopy, gel permeation chromatography, and differential scanning calorimetry.
References
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Advanced Organic Chemistry: Reactions, Mechanisms, and Structure
TL;DR: Localized Chemical bonding Delocalized Chemical Bonding Bonding Weaker than Covalent Stereochemistry Carbocations, Carbanions, Free Radicals, Carbenes and Nitrenes Mechanisms and Methods of Determining them Photochemistry Acids and Bases Effects of Structure on Reactivity Aliphatic Nucleophilic Substitution Aromatic Electrophilic Substitutes Aliphatically Electrophilic Substitution Free-Radical Substitution Addition to Carbon-Carbon Multiple Bonds Adding to Carbon Hetero Multiple Bonds Eliminations Rearrangements Ox
Journal ArticleDOI
Synthesis and characterization of sulfonated poly(ether ether ketone) for proton exchange membranes
Peixiang Xing,Peixiang Xing,Gilles P. Robertson,Michael D. Guiver,Serguei D. Mikhailenko,Keping Wang,Serge Kaliaguine +6 more
TL;DR: In this article, a series of sulfonated poly(ether ether ketone)s (SPEEKs) were prepared by sulfonation of commercial Victrex ® and Gatone ® PEEK for a comparative study of proton exchange membranes (PEM) intended for fuel cell applications.
Journal ArticleDOI
Syntheses and characterization of heteroatom-bridged metal-free phthalocyanine network polymers and model compounds
TL;DR: In this paper, le polymeres et composes modeles ont une resistivite electrique elevee and ne peuvent etre dopes par l'iode.
Journal ArticleDOI
Synthesis and properties of a bisphenol A based phthalonitrile resin
TL;DR: In this article, a multiple aromatic ether linked phthalonitrile was synthesized and characterized, which exhibited good structural integrity upon heating to elevated temperatures and exhibited excellent thermal properties along with long-term oxidative stability.
Journal ArticleDOI
Phthalonitrile cure reaction with aromatic diamines
Satya B. Sastri,Teddy M. Keller +1 more
TL;DR: In this paper, a sulfone-containing diamine, bis[4-(4-aminophenoxy)phenyl] sulfone (p-BAPS), was used for phthalonitrile cure.