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Starting a new undertaking, it is only natural to look back on the history and predecessors. For me, as a second Editor-in-Chief of Journal of Reinforced Plastics and Composites (JRPC) it is a humbling experience. My direct – and only – predecessor, Professor George S. Springer from Stanford University, USA, not only founded the journal but also successfully led it for more than four decades. So, it is worthwhile looking at the importance of this period for the field of composite materials to better appreciate its swift development. In 1987 (i.e. five years after the JRPC start), M.F. Ashby stated
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that the use of materials ‘in the past 20 years … has changed’ as a result of a fast introduction of high-strength polymers and structural composites (ceramics were also mentioned). Interestingly, Ashby starts the history of composites (in the form of ‘straw bricks’) from ‘before 2000 B.C’. Without a detailed historical analysis, using only Scopus as a tool, it can be found that the first scientific paper related to composites is from 1938,
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spearheading the trajectory of the field in the 1960s. This is clearly demonstrated by the evolution of the number of publications in the areas of reinforced plastics and composite materials (based on the Scopus data) – see Figure 1 and Table 1. From 1982 to 2025, according to Scopus, the annual number of publications increased by a factor of slightly more than 10. For our two topics of interest – reinforced plastics and composite materials – the respective factors were 38.4 and 13.1. Increase in number of publications on reinforced plastics (RP) and composite materials (CM) worldwide (based on Scopus data). The red vertical line corresponds to the start of publication of JRPC in 1982 (the photo is of its first Editor-in-Chief Prof. George S. Springer). Number of publications on reinforced plastics and composite materials.
This rise was reflected in the introduction and development of dedicated scientific journals, with Mechanics of Composite Materials established in 1965, Journal of Composite Materials in 1967, Composites Science and Technology in 1968 (as Fibre Science and Technology), Composites (that later became Composites Part A: Applied Science and Manufacturing) in 1969 and Polymer Composites in 1980. Composites Structures was founded in 1983, one year after JRPC.
JRPC started in 1982 with publication of four issues and 28 papers. In 2025, 24 issues were published with 184 papers (this was a decline from 240 papers in the previous year). The papers in the very first issue of JRPC (seven in total) covered various topics related to the plastics and polymers. The opening paper 2 dealt with spherical inclusions in an elastic matrix, calculating the effective magnitudes of the Young’s modulus and the Poisson’s ratio of this composite. The use of theoretical methods to obtain properties of composites based on a single-particle approximation continued in a two-part paper on damping characteristics of fibrous composites with a slip at a fibre/matrix interface.3,4
Numerical simulations were also prominently presented with two papers. One focused on the assessment of effective stiffness properties of a composite with finite-element (FE) simulations based on approximate values of parameters that were subsequently adjusted by using the Newton-Raphson method and experimental data. 5 For younger readers probably the most surprising feature would be the number of elements used – 2 × 4 for a ‘cantilever plate’ and 4 × 4 for a simply supported plate. Another paper 6 suggested an improvement for the FE method by applying a finite-prism-strip approach to analysis of sandwich panels since it can ‘save considerable computing effort than the finite element method’. The largest number of the finite-prism elements for a case of ‘commercial type of formed face sandwich panel’ was 10. Interestingly, these computational papers also had considerable theoretical parts linked to the used simulation methods.
Experimental approaches also found their way into the first issue of JRPC. As expected, they considered the problems that were hard to deal with within the framework of theoretical or numerical schemes, mostly based on linear properties and formulations. One paper 7 discussed the time-dependent behaviour – creep, recovery and relaxation – of epoxy-nitril and modified epoxy adhesives in bonded joints (with thick aluminium adherends) and assessed parameters of a four-element structural viscoelastic model. This model was used subsequently in an in-house computer program to analyse the evolution of shear strains in a double-lap joint in comparison with direct experimental measurements. The second experimental paper 8 investigated the effect of volume fraction of fillers and heating regimes on thermal properties (glass transition temperature and heat capacity) of iron-epoxy composites.
Let us now fast-forward to the present time. The first (but double) issue of Volume 45 from January 2026 has 32 papers. Its first apparent feature is a considerably broader range of materials and even material classes. Five papers deal with “nano’ – nanocomposites (three) and carbon nanotubes (two), while another three include ‘bio’ in their titles (bio-derived matrices). More non-traditional fillers are used: alongside the already mentioned nanotubes, there are organoclay, graphene and a combination of MoSi2 and SiB6 – or even straw fibres (see the history trial by Ashby above) and pistachio shell particles. Hybridisation also plays a prominent part, with six papers discussing effects of, for example, combined Kevlar and basalt fibres, hybridised matrix or hybrid matrix structures.
The present-day issue of JRPC deals also with a much broader range of properties and performances of reinforced polymers and composites as well as their loading and environmental conditions. The papers in this issue study impact resistance, flame retardancy, tribological performance and oxidation resistance of such materials as well as propagation of stress waves in them. Among non-traditional environments, the challenging conditions related to laser shocks, elevated-temperature wet conditions or seawater are also analysed. Another feature – naturally absent in 1982 – is research into 3D printing of composites, with three papers on this topic in the first issue of 2026. Obviously, the number of finite elements used in numerical analysis increased considerably (e.g. 40,000 in 9), but there is still some place for theoretical approaches, for instance, using the Burger model and De Gennes’s scaling theory to describe the polymer/particle interphase region around nanoparticles. 10
These differences between the past and the present – using an example of respective issues of JRPC – demonstrate the reasons for developments in the field of composites in the last four decades that – together with a global expansion of academia and research – resulted in a huge increase of publications. Here, several important – and in many cases interconnected – general trends in the area of reinforced plastics and composites can be mentioned: (1) A much broader range of materials is now used for matrices and reinforcement, including both novel advanced engineering materials and bio-derived ones. Nanofillers (and, as results, nanocomposites) are extensively developed and introduced. In parallel, an increased use of thermoplastics in various products accompanies the traditional use of thermosets in aerospace, automotive, energy, defence, sports and other applications. (2) Not only the number of potential constituents increased; hybridisation made the number of potential combinations of matrices and reinforcements significantly higher, with this approach applied not only to fillers but also to matrices and structures. (3) Additive manufacturing (AM) (commonly known as 3D printing) revolutionised the production of complex shapes and structures, with a nearly infinite design freedom, in parallel with the extended use of traditional laminates. As a result, micro-architectured composite materials, components and structures are designed with special properties or for specific purposes. AM also provides additional opportunities for creation of functionally graded materials. (4) The use of constituents with complex multi-physics properties caused the emergence of functional (or smart) composite materials. This, together with AM, allowed the development of 4D printing of composites capable to change their shape, properties or performance with time (which is the fourth ‘D’ in ‘4D’; some researchers mention 5D and even 6D printing, but here the number of Ds is increased due to the growing number of axes – degrees of freedom in printing robotic systems). (5) A traditional drive in science and technology – due to the need for continuously increasing usability envelopes – resulted in exposure of reinforced plastics and composite materials to harsher environments, requiring the development of materials specifically for extreme conditions. These conditions include high and low temperatures; high forces, deformations and strain rates; exposure to water, hydrogen and various chemical substances; and physiological conditions inside the body (for biomedical applications). (6) Not only harsh environments mentioned in point 5 above, but also long-term exposure to ‘normal’ temperatures and air usually affects reinforced plastics and composites significantly more than other types of materials – metals and alloys, and ceramics. Hence, the effects related to the aging process have become more important. In the form of degradation (or biodegradation), they can play either a negative role, diminishing structural integrity and/or functionality of components and structures, or a positive one in matters related to recycling and sustainability. This is especially important for green or bio-composites.
All these factors resulted in a considerably broader use of polymer-based components and structures in many applications, from traditional to novel ones. So, these trends caused us to consider the future. As a result, to reflect the latest developments and trends, JRPC adjusted its Aims and Scope. Obviously, it will continue to deal with polymers (with or without fibre or particulate fillers) intended for increasing engineering and biomedical uses, including automotive, aerospace, naval and energy industries, building and constructions, biomedical devices and sensors, and electronic and electrical applications. An additional focus will be on novel materials (including biopolymers and green composites), as well as advanced functional polymers and smart composites.
The advent of machine learning and artificial intelligence provided a new way to deal with the description and effects of complex microstructures (both in terms of topology and morphology of reinforcement). This could significantly accelerate the – traditionally challenging and time-consuming (consider multi-scale theoretical or numerical homogenisation) – assessment of effective properties of composite materials and even their performance and structural integrity. Another important opportunity linked to Big Data – together with the new freedom to shape the microstructure with high precision and control using advanced manufacturing techniques – is materials design, aiming at specific properties, performance and/or functionalities.
The novel use of new advanced materials will require assessment of effects of different (and, in many cases, harsh) environments, enhancing traditional stress analysis at various length and time scales with multi-physics approaches. The long-term use – or durability analysis – of composite structures and components requires direct account for their ageing (and respective deterioration of mechanical properties and functionality) both in experimental programs and theoretical studies.
In the area of manufacturing, a broad use of various AM techniques (especially, material-extrusion-based) will not only affect the design of new materials and structures but also underpin the search for their new applications. Another important matter is recycling of composites, including the use of recycled constituents.
Undoubtedly, the rapid development of the field of reinforced plastics and composites, vividly demonstrated during its relatively short history, will continue in the future. The emerging new challenges, solutions and applications will be an important contribution to science and technology, and JPRC will continue playing its important part in this.
