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Injection moulding is one of the most important processes of plastics and rubber compounds processing. It enables the production of very complex plastics and rubber parts, even parts made of different plastics and rubber compounds, in one cycle. The system for injection moulding of polymers consists of different elements such as the mould, injection moulding machine and device for mould temperature regulation (tempering), and additional elements: dryers, robots, etc. For successful injection moulding, optimisation of moulded part material selection as well as elements of the injection moulding system is necessary. All of the mentioned factors consume signifi cant amounts of energy. The paper presents the analysis of energy consumption in injection moulding systems, as well as the possibilities of energy savings in injection moulding process, starting with material selection, in order to obtain a more energy effi cient process. [ABSTRACT FROM AUTHOR]

Injection moulding is one of the most important processes of cyclic polymer and other materials processing. It enables the production of very complex parts, in one cycle. For successful injection moulding, injection moulding system is necessary. It consists of main elements: the mould, injection moulding machine and device for mould temperature regulation (tempering), and additional elements: dryers, robots etc. All of the mentioned elements consume significant amounts of energy. The paper presents the analysis of the possibilities of energy savings in injection moulding process, starting with moulded part geometry, in order to obtain more energy efficient process. [ABSTRACT FROM AUTHOR]

The paper presents phases of the development from the idea to the final product using the case of a letter opener which contains the visual identity (logotype) of the Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, which has been adapted for the ninetieth anniversary of the Faculty. [ABSTRACT FROM AUTHOR]

In today's world environmental protection plays an important role. This also includes the rivers, lakes, seas and oceans. The general problem in the seas and oceans, among other things, are the discarded plastic products. Such fl oating plastic products act as absorbers of heavy metals, pesticides, polychlorinated biphenyls (PCBs) and other toxins that then get accumulated in sea animals, and consequently in humans as well. The most common sources of pollution are the ships (35 to 85%), i.e. people who throw various products into the sea, lost fi shermen's nets and waste from rivers or brought by the wind. The need to reduce the quantities of discarded non-degradable plastics in sea, has led to the development of marine degradable materials that after having been discarded into water (sea, lake and river) degrade completely after a certain time. The paper analyzes the possibility of processing the marine degradable material using the injection moulding process, and also the testing of mechanical properties has been performed. Its degradability in the sea has been tested as well as the applicability of the material for manufacturing of products that come into close contact with food. [ABSTRACT FROM AUTHOR]

According to the great impact of additive technology on the development of modern industry, a lot of research is being done to obtain 3D printed parts with better properties. This research is extremely important because there are no scientific papers in the field of post dyeing of acrylonitrile/butadiene/styrene (ABS) 3D printed parts. The experiment was carried out using disperse dyes on ABS specimens. The obtained coloration of the specimens was in the primary colors (yellow, red, and blue) in the specified dyestuff concentration range and was evaluated using an objective CIELab system. Based on the obtained color parameters, remission values and Kubelka-Munk coefficient, dye mixtures and an ombre effect were performed to obtain patterns in the desired hues. Abrasion resistance of disperse dyed specimens was tested using different abrasive materials over a wide range of fineness to simulate different indoor and outdoor soils and was compared to abrasion resistance of specimens produced from the industrially dyed wire with the master batch. The results show that 3D printed ABS products can be produced in one or more desired shades with satisfactory abrasion resistance. This undoubtedly represents the added value of 3D printed ABS parts and extends their application to the field of creative industries and design, specifically footwear design. [ABSTRACT FROM AUTHOR]

Based on the philosophic ideas of O. Spengler and Aristotle it has been determined that polymers are ancient since they reach back all the way to the origin of the basic natural organic and inorganic polymers. At the same time it has been noted that the word polymers is frequently used as a common name for plastics and elastomers. Since the basic natural organic polymers: proteins, nucleic acids, and polysaccharides there is a long historical path. An attempt was made to present this path by means of a flow chart. For the mentioned description numerous definitions are required, as well as a motivating basis. This was done in Annexes A and B. The conclusion of the research is that primary shaping and primary structuring of natural polymers is around 3.5 billion years old and human separation with natural tools about 3.4 million years. Anyone involved in polymers should be educated at an adequate level of the necessary knowledge with the developed flowchart. [ABSTRACT FROM AUTHOR]