This article discusses the results of experimental research on the synthesis of polyether sulfones and the molten polymer filament layering 3-D printing technology. The regularities of influence of the polycondensation conditions in the synthesis of polyphenylene sulfone on the processes of cross-linking, thermal degradation of the polymer at processing temperatures, and 3-D printing were revealed. It is shown that introduction of cardo fragments increases the glass transition temperature and heat resistance of the copolymers, and the elastic-strength properties, due to the increased chain rigidity. It determined the influence of technological modes of 3-D printing by layering molten polymer filaments on the physico-mechanical properties of polyether sulfones.

The regularities of branching and thermal destruction processes of polysulfones of different chemical structure at 150–500°С are studied depending on the nature of the reactive medium and blocking method of the terminal groups with the use of a special device for a gas chromatograph allowing one to investigate the branching and thermal destruction of polymers. It is found that the nature of the solvent and deactivator of the terminal hydroxyl groups substantially affects the crosslinking and destruction processes of polysulfones.

Purpose: This paper aims to examine the impact of three-dimensional (3D) printing technological modes (using fused deposition modelling [FDM]) on physical and mechanical properties of samples from polyphenylenesulfone. Design/methodology/approach: For this study, the standard test samples were printed using the FDM method at different filament orientation angles, the gaps between them and a different width. The basic physical and mechanical properties, such as the strength, the elastic modulus and the impact strength, were studied. Findings: The authors found that the basic mechanical properties strongly depend on the printing settings. In particular, the elastic modulus generally depends on the air gap between rasters, and it is practically independent of the filament orientation angle. In contrast, the impact strength depends on the orientation and the degree of adhesion between filaments: the highest values are reached at the longitudinal orientation of rasters in the sample (0°) and the minimum value of the air gap (−0.025 mm). However, in selecting the optimal mode of 3D printing, it is necessary to take into account the specific geometry of the printing products and the direction of the stress that it will experience. Originality/value: The paper presents the results of the investigation of the influence of FDM printing modes on the mechanical properties of samples from polyphenylenesulfone, including impact strength. The authors studied the mechanisms of the destruction under impact loading and revealed the optimal printing settings for making samples with properties which are not inferior to the injection molded samples.

In this work, PPSUs with different molecular weights were synthesized for the development of highly permeable ultrafiltration hollow fiber membranes for the first time. The M_W of the synthesized polymers was controlled by varying the monomers molar ratio within 1:1–1.15 under the same synthesis conditions. Based on the study of the rheological properties of polymer solutions, a high molecular weight PPSU (M_W = 102,000 g/mol) was chosen for the formation of hollow fiber membranes. The addition of PEG400 to the spinning solution led to an increase in viscosity, which makes it possible to work in the region of lower PPSU concentrations (18–20 wt. %) and to form membranes with a less dense porous structure. With the addition of PEG400 to the spinning solution, the membrane permeance increased sharply by more than two orders of magnitude (from 0.2 to 96 L/m²·h bar). At the same time, the membranes had high rejection coefficients (99.9%) of Blue Dextran model filtered substance (M_W = 69,000 g/mol).