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To evaluate the efficiency of complex esters as plasticizers in polyvinyl chloride plastisols and plasticates.

Several poly(vinyl chloride) plastisols and plasticates were prepared with standard phthalate plasticizers and complex esters and were characterised using standard and laboratory methods.

The use of mixtures of three new CE with standard phthalate plasticizers increased the physical, mechanical and electric characteristics of the resulting PVCPs and PVCPl.

The use of three new CE, obtained by esterification of dicarboxylic acids (adipic, sebacic, pelargonic), poly(ethylene glycol) and i‐octanole, as plasticizers of poly(vinyl chloride) plastisols and plasticates was investigated. The use of CE based on other organic acids could be explored.

The results confirmed the efficiency of plasticization of PVC by CE. Such a finding has significant industrial implication.

Several findings are original and are of importance to relevant industry. The new CE with high molecular weights were effective plasticizers of PVC. The efficiency of the plasticizers depended on their chemical structure. The molecular weight of the CE had no influence on the compatibility of plasticizers and other components of the PVC plastisols and plasticates.

This paper seeks to investigate the influence of chemical structure of ester basestock (trimethylolpropane pelargonate) on the viscosity characteristics of formulations obtained and the operating mechanism of two widely used viscosity index improvers – poly(butadiene‐styrene) and poly(alkyl methacrylate).

Oil formulations of trimethylolpropane pelargonate and poly(butadiene‐styrene)/poly(alkyl methacrylate) as viscosity index improvers are prepared. Their kinematic viscosity at different temperatures is measured. Relative, intrinsic and characteristic viscosities are calculated from the experimental data.

The thickening ability of linear polymers from butadiene‐styrene and alkyl methacrylate in a synthetic oil of ester type (trimethylolpropane pelargonate) is clarified. The conformation of these polymers is studied. Results of comparative tests about the influence of the type of polymer and solvent on characteristic and intrinsic viscosity are presented. It has been established that with the increasing of temperature the quality of used synthetic oil decreased and the characteristic viscosity decreased for both polymers. At lower temperatures the intermolecular interaction between the polymeric macromolecules becomes bigger than their interaction with the molecules of solvent. Molecule associates have been possibly formed at low temperature. These associates increase the viscosity of solutions and this increase is bigger at low temperatures in comparison with high temperatures.

Viscosity index improvement of poly(butadiene‐styrene) and poly(alkyl methacrylate) is determined. The information about concentrations and viscosity is of practical interest.

The combination of these synthetic basestock and viscosity index improvers is a new one. The data obtained may have value for the oil production.

The aim of this study is the synthesis and characterization of motor and hydraulic oils based on complex esters of dicarboxylic acids and polyol esters. The esters have been prepared by polyesterification of adipic or sebacic acids with polyethylene glycol and by subsequent reaction with 2‐ethylhexanol using a new high active catalyst tetraoktyltitanate (TOT)‐TlCl. The synthesis of pentaerythritol esters of monocarboxylic acids has also been undertaken in the presence of the same catalyst. The catalyst reduces the time and temperature required for the reaction to produce esters with characteristics of standard motor and hydraulic oils.

The purpose of this paper is to research the durability of the adhesive‐poly(ethylene terephthalate) film joints.

The adhesive‐poly(ethylene terephthalate) joints are prepared with poly ethylene terephthalate film synthesised from thioglycolic acid, terpene hydrocarbon resin and acetone resolution at room temperature. These joints are characterised by methods of peel strength tests, energy dispersive X‐ray spectroscopy (EDX) and analysis of glass transition temperature (T_g) to examine their durability.

Peel strength tests and EDX analyses prove that water diffusion in different humidity aging conditions causes similar changes, namely having the time‐temperature equivalence at 45°C for 200, 300, 500 and 600 h, respectively, almost corresponding with those at 55°C for 100, 200, 300 and 400 h, respectively, and at 65°C for 50, 100, 150 and 200 h, respectively. The changes in EDX spectra of adhesive‐poly(ethylene terephthalate) film joints indicate that the rate of water penetration in the adhesive is faster than that in the poly(ethylene terephthalate) film. In humidity aging process, the decline ratio of peel strength of adhesive‐poly(ethylene terephthalate) film joints treated with Co⁶⁰ irradiation is lower than that treated with acetone washing or chemical treatment.

The paper shows that using EDX for analysis of durability of adhesive film joints is of significance to industrial process.

This paper aims to discuss the successful 3D printing of styrene–ethylene–butylene–styrene (SEBS) block copolymers using solvent-cast 3D printing (SC-3DP) technique.

Three different Kraton grade SEBS block copolymers were used to prepare viscous polymer solutions (ink) in three different solvents, namely, toluene, cyclopentane and tetrahydrofuran. Hansen solubility parameters (HSPs) were taken into account to understand the solvent–polymer interactions. Ultraviolet–visible spectroscopy was used to analyze transmittance behavior of different inks. Printability of ink samples was compared in terms of shape retention capability, solvent evaporation and shear viscosity. Dimensional deviations in 3D-printed parts were evaluated in terms of percentage shrinkage. Surface morphology of 3D-printed parts was investigated by scanning electron microscope. In addition, mechanical properties and rheology of the SC-3D-printed SEBS samples were also investigated.

HSP analysis revealed toluene to be the most suitable solvent for SC-3DP. Cyclopentane showed a strong preferential solubility toward the ethylene–butylene block. Microscopic surface cracks were present on tetrahydrofuran ink-based 3D-printed samples. SC-3D-printed samples exhibited high elongation at break (up to 2,200%) and low tension set (up to 9%).

SC-3DP proves to be an effective fabrication route for complex SEBS parts overcoming the challenges associated with fused deposition modeling.

To the best of authors’ knowledge, this is the first report investigating the effect of different solvents on physicomechanical properties of SC-3D-printed SEBS block copolymer samples.