Phthalonitrile Resins for High-Temperature polymer matrix Composites (HTCs)

At SPECIFIC POLYMERS, our R&D is at the forefront of developing high-performance composite materials tailored for demanding sectors like aeronautics and aerospace.

Our dedicated team of researchers is spearheading the creation of resins engineered for exceptional thermal resistance, crucial in these high-stakes environments.

Driven by a commitment to technological excellence, we tackle the industry’s toughest challenges, delivering advanced materials that elevate both performance and processability.

PHTHALONITRILE RESINS – THERMOSTABLE ORGANIC MATRICES

Phthalonitrile resins, a type of thermosetting resin, are increasingly gaining attention due to their properties such as high thermal and thermo-oxidative stability, low water absorption, outstanding mechanical properties, and exceptional fire resistance.[1]

In composites, the thermosetting resin serves to bind fibers together and ensure material resistance against mechanical degradation, which significantly influences compression, flexural, and shear properties. Currently, epoxy resins dominate as the matrix material for numerous composites application. However, these matrices lack sufficient thermal stability for applications requiring mechanical performances above 250°C.

To address this temperature range, several resin types have been identified in scientific literature, such as cyanate esters,[2] bismaleimides,[3] and polyimides.[4] After extensive research and evaluation, SPECIFIC POLYMERS has chosen to focus its R&D efforts on phthalonitrile resins.

Phthalonitriles have seen substantial growth in high-performance materials over the past three decades. Besides exhibiting low moisture absorption and fire resistance, these resins exhibit excellent thermo-oxidative stability and can withstand temperatures exceeding 300°C over prolonged periods while retaining material properties. These exceptional thermal properties stem from their aromatic composition and highly stable cross-linking sites. Moreover, phthalonitriles cross-link via a mechanism that minimizes the release of volatile species, thereby reducing material defects.

Over the past 5 years, SPECIFIC POLYMERS has developed phthalonitrile compounds that may be of interest in designing formulations of cross-linkable resins that can be adapted to various processing methods and different high demanding applications. The impressive thermal stability of these resins stems from the extensive aromaticity of the organic matrix after cross-linking. While this network type tends to be less flexible at room temperature due to limited network mobility, optimizing these properties is key to creating resins that meet the specific needs of each application.

Overview of current heat-resistant resins – the dilemma between excellent mechanical properties and high continuous use temperature

The high thermal stability characteristic of these resins results from the extensive aromaticity of the organic matrix post-cross-linking. However, a drawback of this network type is the inherent brittleness of the materials, particularly at room temperature, due to very limited network mobility. Balancing these factors is crucial in formulating resins tailored to each application’s requirements. Our development efforts are focused on figuring out this optimal balance in order to meet the application requirements of our customers.

Corresponding Scientific Publications

[1] Bo Liang et al., Kinetics of the pyrolysis process of phthalonitrile resin, Thermochimica Acta, 672, 133-141 (2019) >

[2] Kessler, M.R., Cyanate Ester Resins Adapted from Cyanate Ester Resins, First Edition, in Wiley Encyclopedia of Composites. p. 1-15 (2012) >

[3] Iredale, R., C. Ward, and I. Hamerton, Modern advances in bismaleimide resin technology: A 21st century perspective on the chemistry of addition polyimides, Progress in Polymer Science, 69 (2016) >

[4] Harvey, B.G., et al., Synthesis and characterization of a high temperature thermosetting polyimide oligomer derived from a non-toxic, sustainable bisaniline, RSC Advances, 7(37): p. 23149-23156 (2017) >

PHTHALONITRILE BUILDING-BLOCKS AVAILABLE AT SPECIFIC POLYMERS

The research conducted by SPECIFIC POLYMERS in recent years has enabled us to offer a range of Phthalonitrile compounds for sale. Following Phthalonitrile compounds are characterized by diverse functionalities, allowing you to design and tailor material properties according to your specific application needs.

Currently, these products are available in quantities ranging from 10 to 100 grams depending on each reference, with bulk quantities available upon request.

SPECIFIC POLYMERS is committed to support its clients and partners in developing innovative materials and validating proof of concepts. In addition to these building blocks, we can also support you R&D on demand by custom designing high-performance thermomechanical resin formulations.

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DISCOVER OUR FIRST FORMULATED PHTHALONITRILE RESIN SP-3414_A

SP-3414_A is a mono-component phthalonitrile resin specifically tailored for use in processes like vacuum infusion and RTM (Resin Transfer Molding). This phthalonitrile resin offers exceptional thermal stability, high glass transition temperature, flame retardancy, and superior mechanical strength.

SP-3414_A phthalonitrile resin is available at 250g, 500g, 1kg + Bulk on request.

Datasheet SP-3414_A Phthalonitrile resin

Are you interested in this resin range or require our support in this field?

THE STRATEGIC EDGE OF PHTH RESINS AND HTC IN AERONAUTIC AND AEROSPACE

Titanium is essential for the aerospace industry since it is used in high-stress and high-temperature components like engines, landing gears, engine pylons, and wings due to its strength, light weight, and corrosion resistance. Its unique properties make substitution and further improvement toward lightweight material challenging. However, titanium is also becoming increasingly scarce and less sustainable and there is thus a need to develop high thermal performance composite alternatives to keep on improving fuel efficiency, minimize environmental impact, and ensure safety and performance.

High-temperature composite materials (HTCs) have emerged as promising candidates, offering the potential to reduce weight and cost without compromising on performance. HTCs provide up to a 40% weight reduction, leading to fuel savings of hundreds of dollars for every kilogram of titanium replaced per aircraft, along with potential benefits such as extended service life and enhanced fatigue resistance. Such materials can withstand the high stresses and temperatures experienced by aircraft and defense equipment, providing a viable solution for replacing titanium.

Developing these HTC materials for such sector implies rigorous standards and involves overcoming technical barriers related to thermal stability, mechanical strength, and manufacturing processes. This endeavor is crucial for advancing next-generation technologies and maintaining competitiveness in these high-stakes fields.

Additionally, SPECIFIC POLYMERS aims to offer a range of resin systems adaptable to various composite manufacturing processes, including resin transfer molding (RTM), resin infusion molding (RIM), filament winding, prepreg consolidation, and potentially automated composite manufacturing techniques such as automated tape laying and automated fiber placement.

PHTALONITRILES – CHEMICALS OF INTEREST IN NUMEROUS FIELDS OF APPLICATION

Phthalonitrile-based resins offer a remarkable combination of properties, such as resistance to flammability, low water absorption, and high-temperature stability, that are unmatched by other organic materials on the market. When cured, these resins create composites that are ideal for structural applications in harsh, oxidizing environments, making them especially suitable for marine uses. Their fire resistance, particularly in phthalonitrile-carbon and phthalonitrile-glass composites, surpasses that of any other thermoset composites currently used in ships and submarines, expanding their potential in a variety of applications. Additionally, their low water absorption and outstanding stability at high temperatures position phthalonitrile-based polymers as game-changers in industries ranging from lightweight automotive manufacturing to fire-resistant building materials. These properties make phthalonitrile resins highly desirable for diverse applications, including in automobiles, ships, oil rigs, wind turbines, high-temperature bearings, valves, battery and electronic casings, and fire-resistant textiles. [5]

Beyond their use in composites, phthalonitrile-based chemicals have significant potential in other areas of chemistry. Their unique chemical structure and reactivity have sparked interest in applications like the synthesis of metallo-phthalocyanines and corresponding transition metal complexes, which are used in anticancer, antimicrobial, and biologically active materials, [6] [7] as well as in the production of organic dyes and pigments [8]. Moreover, phthalonitrile resins exhibit excellent dielectric properties, including high permittivity and a low loss tangent, making them well-suited for high-temperature applications that require radiofrequency transparency. [9]