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The paper aims to promote the development of intelligent materials and the 4D printing technology by introducing recent advances and applications of additive layered manufacturing (ALM) technology of intelligent materials and the development of the 4D printing technology. Also, an arm-type ALM technology of shape memory polymer (SMP) with thermosetting polyurethane is briefly introduced.

This paper begins with an overview of the development and applications of intelligent materials around the world and the 4D printing technology. Then, the authors provide a brief outline of their research on arm-type ALM technology of SMP with thermosetting polyurethane.

The paper provides the recent developments and applications of intelligent materials and 4D printing technology. Then, it is suggested that intelligent materials mixed with different functional materials will be developed, and these types of materials will be more suitable for 4D printing.

This paper overviews the current developments and applications of intelligent materials and its use in 4D printing technology, and briefly states the authors’ research on arm-type ALM technology of SMP with thermosetting polyurethane.

Corrosion protection has long relied on a number of wet or dry processes including PVC, polyurethane, thermosetting polymer and thermoplastic coatings. Each of these have weaknesses, either in the level of protection provided, durability, cost, or ease of application. The introduction of DuPont’s Abcite ethylene acid copolymer coating represents a major technology breakthrough as it offers a combination of properties with many advantages for a very wide range of applications.

Ten years ago the most favoured pipeline coating system was one based on hot tar enamels and bitumens, then more latterly a dual‐component system such as a thermosetting polyurethane tar, which retained the good adhesion of the straight tar enamels but with improved abrasion resistance and a tough and smooth finish. Polyethylenes were tried in a number of cases and although they gave greater mechanical resistance properties than coal tars and bitumens, which in turn meant that a coating of around 2mm, as opposed to 4 and 6mm, could be used, these polyethylenes lacked adhesion. So much so that an adhesive primer had to be used.

Three-dimensional (3D) printing provides more possibilities for composite manufacturing. Composites can no longer just be layered or disorderly mixed as before. This paper aims to introduce a new algorithm for dual-material 3D printing design.

A novel topology design method: solid isotropic material with penalization (SIMP) for hybrid lattice structure is introduced in this paper. This algorithm extends the traditional SIMP topology optimization, transforming the original 0–1 optimization into A–B optimization. It can be used to optimize the spatial distribution of bi-material composite structures.

A novel hybrid structure with high damping and strength efficiency is studied as an example in this work. By using the topology method, a hybrid Kagome structure is designed. The 3D Kagome truss with face sheet was manufactured by selective laser melting technology, and the thermosetting polyurethane was chosen as filling material. The introduced SIMP method for hybrid lattice structures can be considered an effective way to improve lattice structures’ stiffness and vibration characteristics.

The fabricated hybrid lattice has good stiffness and damping characteristics and can be applied to aerospace components.

This paper aims to disclose the evolution of pendulum hardness of two-component acrylic polyurethane coatings during the cure process and attempts to describe the quantitative relationship between pendulum hardness and curing time. These findings are helpful for the study of fast curing acrylic polyurethane coatings.

The pendulum hardness method was used to monitor the hardness of two-component acrylic polyurethane coatings during curing. The quantitative relationship between pendulum hardness and curing time can be obtained with Avrami equation.

The evolution of coating pendulum hardness can be divided into three stages. By using the Avrami equation that explained the influence of both the acid value and the curing temperature on the drying speed of hydroxyl acrylic resin, the evolution of coating pendulum hardness during curing can also be accurately described.

It should be noted that the physical meaning of the Avrami exponent, n, is not yet clear.

The results are of great significance for the development of fast-curing hydroxyl-functional acrylic resins, with the potential to improve the drying speed of the coatings used in automotive refinish.

It is novel to divide the pendulum hardness into three stages, and, for the first time, the Avrami equation is utilized to describe the evolution of coating pendulum hardness during curing.

The reasons why a coating is selected as suitable for use on a pipeline would normally depend upon two major factors. Firstly, the performance of the available coatings has to be evaluated according to their technical characteristics. Secondly, price, which is more often influenced by application techniques rather than actual material cost.

The following article reports on the use of PUR (polyurethane) systems for the building industry and discusses the choice of PUR raw materials available with particular reference to the surface treatment of concrete facades. One‐pack polyurethanes are used principally for impregnating concrete surfaces and solvent‐free PUR coatings can be made so elastic that cracks in concrete structural components can be bridged. Knifing polyurethane products can be used in the laying of ceramic tiles. Joint sealants can be produced either from two‐pack products or from blocked isocyanate prepolymers, which react with ketimines only in the presence of atmospheric moisture. Epoxy resin coatings are elasticised by blocked prepolymers. Statistics show that 30 per cent of plastics produced in the Federal Republic of Germany are used in the building industry. Nearly all plastics and paint binders are included in this figure. Polyurethane raw materials have also been used for many years. Apart from PUR insulating materials, polyurethanes are used in interior decoration as parquet floor varnishes, where abrasion resistance, flexibility and resistance to chemicals are required.

The inclusion of the word ‘some’ in the above title is essential. When reviewing even a fraction of all the literature dealing with current and likely future developments in the synthetic resins field, it becomes apparent that any paper adequately covering this would be far too long to be of any use in a symposium such as this. It has therefore been necessary to highlight certain aspects which are of a major nature on the one hand and more familiar to the author on the other.

A great deal has been written about the uses of adhesives in industrial and domestic applications, and much progress has been made in recent years in the technology of this important and interesting segment of polymer chemistry. In this article it is not proposed to dwell on the well‐established (and equally well‐documented) adhesives, but rather to highlight newer developments, and particularly those areas in which rapid growth is anticipated or is already taking place.