Gas Separation Properties of the Dense Polymer-Zeolite Powder Composite Membranes

The natural balance in the Earth's atmosphere is significantly influenced by the human emission of the combustion products, mainly carbon dioxide. Therefore, strong efforts are directed in the direction of the reduction of that emission. The solution might be searched in the direction of the construction of the membrane that would be highly transparent to the carbon dioxide, but not transparent to the other gases commonly present in the waste gases (oxygen, nitrogen, hydrogen, methane). One of the feasible designs for this purpose is dense, non-porous membranes, with zeolite particles dispersed in the polymer matrix. Zeolite particles should increase the solubility of the carbon dioxide, and thus enhance its permeability. In this paper, the possibility of application of polyether-b-amide (with 60% of PEG) as a polymer matrix was tested. For the inorganic component, four different zeolite types with three different pore geometries were tested. The influence of the additive which was added in order to provide good contact between the highly polar and charged zeolite inorganic particle, and hydrophobic polymer chains was also tested

Circular economy framework for sustainable product design strategies

Limited global resources, climate changes, growing population, combined with demand for sustainable products, indicate the need for change of existing production and consumption practices. In order of achieving more regenerative, restorative, and circular economy, design has been recognized as a catalyst for moving away from the traditional linear economy model (take-make-dispose). As shifting focus from quantity to quality, and finding new ways of working in cooperation with the nature, slowly becoming paradigm, it is important for designers committed to sustainability to have in mind environmental, social and economic performance of product design. This paper aims to address position of different product design strategies correlated with circular economy concept, as well as the opportunities for designers’ to shift their mindset from the position of creators to solution providers

Green Face of Packaging – Sustainability Issues of the Cosmetic Industry Packaging

Packaging is a steadily growing industry that faces many challenges as well. Ever growing consumer expectations, though competition, technological advances don’t come even close to the huge issue of sustainability within the industry. Packaging for the beauty industry is dependable on the looks more than any other with massive changes in the recent years since extensive grooming became a part both genders lifestyle today and spreading those standards across the globe. The global cosmetic packaging market was valued at USD 25.9 billion in 2018 and is expected grow 4.8% in the next 5 years flying high on the innovative package designs, increasing demand for cosmetics focused on the middle class and youth as well as e-commerce. The first stepping stone is that more than half of the materials used for the massive cosmetic industry packaging are plastics. Finding alternatives and making a shift to a greener and circular way will be a challenge in the years to come

Determination of tension strength in the longitudinal and circumferentional direction in glass-polyester composite pipes

Polymer composite pipes with glass fiber reinforcement have today a wide usage in the chemical and process industries. The basic subject of this paper is the determination and distribution of stresses and strains in longitudinal and circumferentional directions of glass-polyester pipes under tension test. Also, the tension strengths in both directions are determined out. Tension test was performed on an electro-mechanical test machine on flat samples and rings obtained by cutting of pipes produced by the method 'Filament winding' with glass fibers reinforcement ±55°. Also, the micromechanical analysis on fracture surfaces was done by SEM, which provided the knowledge about models and mechanisms of fracture on applyed loading.Cevi od polimernih kompozita sa staklenim ojačanjem danas imaju široku primenu u hemijskoj i procesnoj industriji. Predmet ovog rada je određivanje i raspodela napona i deformacija u uzdužnom i obimnom (tangencijalnom) pravcu staklo-poliester cevi pri ispitivanju zatezanjem. Takođe, određena je i zatezna čvrstoća u oba navedena pravca. Ispitivanje zatezanjem je izvedeno na elektromehaničkim kidalicama na ravnim uzorcima i prstenovima sečenim od cevi proizvedenih metodom namotavanja, sa namotavanjem staklenog ojačanja pod uglom ±55°. Mikromehanička analiza je izvedena na površinama preloma korišćenjem SEM, na osnovu koje su pretpostavljeni modeli i mehanizmi nastanka loma usled primenjenih opterećenja

Circular economy framework for sustainable product design strategies

Limited global resources, climate changes, growing population, combined with demand for sustainable products, indicate the need for change of existing production and consumption practices. In order of achieving more regenerative, restorative, and circular economy, design has been recognized as a catalyst for moving away from the traditional linear economy model (take-make-dispose). As shifting focus from quantity to quality, and finding new ways of working in cooperation with the nature, slowly becoming paradigm, it is important for designers committed to sustainability to have in mind environmental, social and economic performance of product design. This paper aims to address position of different product design strategies correlated with circular economy concept, as well as the opportunities for designers’ to shift their mindset from the position of creators to solution providers

Effect of alkaline solutions on the tensile properties of glass-polyester pipes

Construction materials, traditionally used in process equipment, are today successfully replaced by composite materials. Hence, many pipes are made of these materials. The subject of this study was the influence of liquids on the state of stresses and tensile strengths in the longitudinal and circumferential direction of glass-polyester pipes of a definite structure and known fabrication process. These analyses are of great importance for the use of glass-polyester pipes in the chemical industry. The tensile properties (the ultimate tensile strength and the modulus of elasticity) were tested and determined for specimens cut out of the pipes; flat specimens for the tensile properties in the longitudinal direction and ring specimens for the tensile properties in the circumferential direction. First, the tension test was performed on virgin samples (without the influence of any liquid), to obtain knowledge about the original tensile properties of the material composite studied. Subsequently, the specimens were soaked in alkaline solutions: sodium hydroxide (strong alkali) and ammonium hydroxide (weak alkali). These solutions were selected because of their considerable difference in pH values. The specimens and rings were left for 3, 10, 30 and 60 days in each liquid at room temperature. Then, the samples were tested on tension by the standard testing procedure. A comparison of the obtained results was made based on the pH values of the aggressive media in which the examined material had been soaked, as well as based on the original tensile properties and the number of days of treatment. Micromechanical analyses of sample breakage helped in the elucidation of the influence of the liquids on the structure of the composite pipe and enabled models and mechanisms that produced the change of strength to be proposed.Konstrukcioni materijali tradicionalno korišćeni u procesnoj opremi su danas uspešno zamenjeni kompozitnim materijalima, tako da su i mnoge cevi izrađene od ovih materijala. Uticaj baznih tečnosti na stanje napona i zatezne čvrstoće u uzdužnom i obimnom pravcu staklo-poliester kompozitnih cevi je tema ovog rada. Cevi su definisane strukture i poznatog procesa proizvodnje. Ove analize su od velikog značaja za korišćenje staklo-poliester cevi u hemijskoj industriji. Zatezne osobine (zatezna čvrstoća i modul elastičnosti) su eksperimentalno ispitivane na isečenim uzorcima; ravni uzorci u udužnom pravcu, a uzorci u obliku prstena u obimnom pravcu. Ispitivanje je prvo izvođeno na uzorcima koji nisu bili izloženi uticaju rastvora baza da bi se došlo do saznanja o prvobitnim zateznim svojstvima ispitivanih kompozitnih materijala. Nakon toga, uzorci su stavljeni u rastvore baza natrijum-hidroksida (jaka baza, pH=14) i amonijum hidroksida (slaba baza, pH=12) 3, 10, 30 i 60 dana na sobnoj temperaturi. Nakon toga su ispitivani na zatezanje prema standardnoj proceduri. Poređenje dobijenih rezultata je izvedeno na osnovu rN vrednosti rastvora i broja dana izlaganja rastvorima baza, a na osnovu originalnih zateznih osobina. Mikromehanička analiza se izvodila u odnosu na fotografije sa skening eloktronskog mikroskopa sa prelomnih površina čime se došlo do podataka o uticaju rastvora baza na strukturu kompozitnih cevi i modele i mehanizme koji su dovodili do promene zateznih svojstava

The influence of high and low temperatures on the impact properties of glass–epoxy composites

The aim of this paper is to present the influence of high and low temperatures on the impact properties glass–epoxy composites. The impact strength an is presented for four different glass–epoxy composite structures at three different temperatures, i.e., at room temperature t = 20 °C, at an elevated temperature t = +50 °C and at a low temperature t = –50 °C. Standard mechanical testing was carried out on the composite materials with specific masses of reinforcement of 210 g m-2 and 550 g m-2 and orientations 0°/90° and ±45°. Micromechanical analysis of the failure was performed in order to determine real models and mechanisms of crack and temperature influence on the impact properties