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The main purpose of polymeric mixtures manufacturing is wish to eliminate or reduce drawbacks which polymers are characterised by and also to strive for reduction of the price of expensive polymers with particular very precious properties by mixing them with cheaper polymers but without significant deterioration of their properties. In the work some investigation results have been presented for PA6 which is miscible in viscoelastic state with polymer, with ability to create physical bounds with substances of inorganic as well as organic origins. For this purpose, polyvinylpyrrolidone (PVP) has been used with law molecular weight (10 ± 2,5 thousand). The functionalactive material was prepared with sharp tuning sorption ability across physical modification polycapramide mixed from bipolar polyvinylpyrrolidone in batch – free state, which characterises high ability complex. In the paper, some results of chosen properties of PA with the addition of polyvinylpyrrolidone (PVP) have been presented. In chance of mixing PA6 with PVP forms solution PVP in PA6, to which proper are large intermolecular influence, in this case hydrogen bond. It is possible to foresee that under the influences of large tangent stresses and intermolecular interaction colloidal solution PVP in PA forms with sure homogeneity, after cooling of it the inversion of winding phases is not noticeable In the mixtures on the basis of such polymers the intermolecular interactions occur, and they differently influence parameters of the modified materials. Conducted investigations have proved opportunity of physical modification of PA6 during mixing, in viscoelastic state, with polyvinylpyrrolidone. The modified polymer has dielectric properties and a reduced susceptibility to water absorption. It can be used as an insulation material, in all industrial sectors, including the energy sector.

For examinations, the following mixtures were made out: PA 99%/PVP 1%, PA 98%/PVP 2%, PA 90%/PVP 10%. Making mixtures out was begun with weighing elements out on numerical Sortorius AG GO TTINGEN scales and CAS MODEL: SW-1 (PA, PVP). Next elements of mixture were mixed with themselves mechanically. The process of drying was carried out in the ZELMET drier with the thermal kc-100/200 chamber in the temperature 80 °C for 12 h. The process of mixing up was carried out in the arrangement plasticising injections moulding machine of the voluted KRAUSS MAFFEI company KM 65-1600C1 (D screw = 30 mm and the L = 27D, the nozzle about d = 4 mm and the l = 2d) at the following parameters: is the nozzle temperature 230 °C, the speed of turnovers of the screw 210 obr/min. Granulated product of mixtures were get on the rotor grinder. Samples for examinations were made on the computer-operated injection moulding machine of type of KM 65-1600C1 of the KRAUSS MAFFEI company. The conditions which complement the homogeneity of a mixture – these include mixing processes with high shear stresses with the range of temperatures for viscoelastic state for the individual polymers. Such conditions are met by multiple mixing in the injection machine cylinder with extended perpetual screw length (L/D = 25 ÷ 42). Permanent conditions of injecting samples for the research on physical properties were the following: nozzle temperature – 230°C; worm area I temperature – 190°C; worm area II temperature – 210°C; worm area III temperature – 230-245°C, mould temperature 40°C, injection pressure – 60 MPa, clamping time – 5 s, cooling time – 30 s The research on chosen physical properties of getting polymer materials was carried out: hardnesses on hardness testing machine, impact resistance by Charpy’s method, mechanical properties while tension over the endurance machine the INSTON with tension speed of 90 mm/min, softening point by Vicat’s method was determined using testing machine type HAAKE N8, the investigation of DSC method and DMTA method using testing machine type Netzsch, water absorbing power test. The research on the structure was also carried out on the optical microscope type NIKON ECLIPSE E200.

In the paper, for the physical modification of PA 6, the polyvinylpyrrolidone (PVP) – amorphous polymer which is capable of ionisation and creation of complexes with the transition of the charge with many electrophilic compounds and also proton donors have been used. PVP does not change into the viscoelastic state but it is easily soluble in organic and inorganic solvents and the best in water. Its characteristic is high sorption capacity. As a result of ionisation changes PVP preserve the conformation changes. In case of mixing of polar PA6 polymers with PVP, a PVP solution is being created in PA, to whom big intermolecular interactions are proper for, in it hydrogen bonds. Reducing of polarity occurs of both polymers as a result of hydrogen bonds in created macromolecules. Macromolecule so they are interfering easily in fused condition creating the mixture about reliable homogeneity. An effect is applying to mixing with PA6 in case of dissolving PVP in the PA6 stop under the influence of big adjacent tensions in screw extruder what is calling changes of the supermolecular structure and properties of the material after chilling of stop in the form during injecting. The resultant homogeneous mixture is marked by one reflex narrowed in comparison with output PA6 of melting visible on DSC thermogram with moving to the page of higher tmmax temperatures. PA6/PVP mixtures are also providing effects of examinations about the homogeneity with DMTA method which shows results that the mixture is marked by one reflex of mechanical losses on the plot from (T_g) from the maximum at bigger than PA6 T_g (about 10 ÷ 15°C), and it is possible at the same time to reason that the mixture has not very thick frictional network as a result of the exchange of intermolecular bonds what is displayed itself in the increase in T_g intensity. The results of investigations show that PA with PVP additions create more stable material with visible homogeneity (due to strong intermolecular interactions) which is characterised by satisfactory mechanical properties which insignificantly differ from PA6 properties, but which shows higher deformability and sorptive power.

The results of investigations show that PA with PVP additions create more stable material with visible homogeneity (due to strong intermolecular interactions) which is characterised by satisfactory mechanical properties which insignificantly differ from PA6 properties, but which shows higher deformability and sorptive power. The modified polymer has dielectric properties and a reduced susceptibility to water absorption. It can be used as an insulation material, in all industrial sectors, including the energy sector.

The purpose of this study is to improve the mechanical and tribological performance of polypropylene (PP) material. The influence of hexagonal boron nitride (h-BN) microparticles on mechanical and tribological properties of PP/polyamide 6 (nylon 6) (PA6) blend has been investigated in this paper.

Tensile strength, elongation, elastic modulus and Rockwell hardness were measured to identify the mechanical properties of materials. Coefficient of friction (COF) and wear rates of materials were measured with the help of a pin-on-disc tribometer to check the tribological behavior of blend and composite materials.

As a result, a small decrease in tensile strength and elongation and improvement in elastic modulus were found for PP/PA6 and PP/PA6/h-BN composite compared to pure PP. The wear rate of PP/PA6 blend and PP/PA6/h-BN composite was found low compared to pure PP matrix, while the COF of PP/PA6 blend was found slightly higher owing to the presence of harder PA6 matrix which was then improved by the h-BN filler reinforcement in PP/PA6/h-BN composite. The addition of PA6 in PP improved the wear rate of PP by 8–24%, whereas the addition of h-BN microparticles improved the wear rate by 22–50% and 24–44% compared to pure PP and PP/PA6 blend, respectively, in different parameters.

Modulus of elasticity and hardness of pure PP was enhanced by blending with PA6 and was further improved by h-BN fillers. The addition of PA6 in PP improved the wear rate, while h-BN fillers were found effective in reducing the COF by generating smooth thin lubricating film.

3D printing techniques such as material extrusion based additive manufacturing provide a promising and cost effective manufacturing technique. However, the main challenges in industrial applications remain with the quality assurance of mass produced parts. The purpose of this study is to investigate the effect of compression moulding as a rapid consolidation method for 3D printed composites, with an aim to reduce voids and defects and thus improving quality assurance of printed parts.

To develop an understanding of the inherent voids in 3D parts and the influence on mechanical properties, material extrusion additively manufactured (MEX) parts were post consolidated by using compression moulding at elevated temperature.

This study comparatively investigates the influence of carbon fibre length, undergoing process induced scission during filament extrusion and IM and its impact on void content and mechanical properties. It was found that the post consolidation significantly reduced the voids and the mechanical properties were significantly improved compared to the nonconsolidated material extrusion additively manufactured parts, reaching values similar to those of the IM parts.

Adaptation of extrusion-based additive manufacturing with hybridisation of reliable compression moulding technology transcends into series production of highly adaptive end user applications, such as drones, advanced sports prosthetics, competitive cycling and more.

This paper adds to the current understanding of 3D printing and provides a step towards quality assurance for mass production.

The purpose of this study is to look into the hygroscopic and tribo-mechanical properties of a polypropylene/polyamide-6 (PP/PA6) blend and a PP/PA6/Boron sesquioxide composite.

The hygroscopic behaviour of the PP/PA6 blend and PP/PA6/Boron sesquioxide composite was studied using a water contact angle goniometer in this study. To validate the hygroscopic behaviour of the blend and composite, water contact angles and surface energy of the materials were investigated. Tensile strength and hardness tests were used to determine mechanical characteristics, and tribological experiments on a pin-on-disc tribometer were used to demonstrate the friction and wear rates of dry and water-conditioned blends and composites. The melting temperature of dry and water-conditioned composites was determined using DSC analysis.

The hygroscopic effect of the PP/PA6 blend was found to be minimal in the experiment, while it was relatively dominating in the PP/PA6/Boron sesquioxide composite. Tensile strength was found to be somewhat lower in blend and composite compared to virgin PP, whereas hardness was found to be higher in both blend and composite. The composite’s tribological testing findings were fairly outstanding, with the coefficient of friction (COF) and wear rates significantly reduced due to boron sesquioxide reinforcement. The reaction between boron sesquioxide and water molecules produced boric acid, which increased the tribological characteristics of the composite even further. Following 30 days of water conditioning, the weight of the blend increased by 3.64% and the weight of the composite increased by 6.45% as compared to the dry materials. After water conditioning, tensile strength reduced by 0.8% for the blend and 14.16% for the composite. Hardness was determined to be the same in the dry state and after water-conditioning for blend but dropped 1% for composite. As compared to blend, the COF and wear resistance of composite were 15.52% and 25.16% higher, respectively. After absorbing some water, the results increased to 28.57% and 34.9%, respectively.

The mechanical and thermal behaviour of polymer composites (particularly polyamide composites) vary depending on the surrounding environment. Tests were carried out to explore the effect of water treatment on the tribo-mechanical and thermal characteristics of PP/PA6/Boron sesquioxide composite. Water treatment caused polyamides to bind with water molecules, resulting in voids in the material. The interaction between boron sesquioxide and water molecules produced boric acid, which increased the tribological characteristics of the composite.

The absorption of moisture/water can affect the mechanical and thermal properties of polymers and polymer composites as many polymers, mainly polyamide thermoplastics, are sensitive to environmental humidity and can absorb a large amount of moisture. This paper investigates the effect of water molecules' absorption on mechanical and thermal properties of polyamide6/hexagonal boron nitride (PA6/h-BN) composites.

The PA6/h-BN composites were exposed to an open environment and water for 15 days to analyse the effect of humidity/water molecules' absorption on mechanical and thermal properties. The tensile strength, hardness and impact strength of materials were measured and compared. The scanning electron microscopy (SEM), x-ray diffraction (XRD) and differential scanning calorimetry (DSC) analyses were utilized to see the influence of water absorption on microstructure, crystallinity and glass transition temperatures.

After exposing materials to an open environment and water, the tensile strength and hardness were found to decline, while improvement in impact strength was noticed. SEM characterization revealed the formation of voids/pockets in water-immersed materials. DSC analysis revealed the loss in glass transition temperatures, and XRD analysis revealed the loss in crystallinity of water-immersed materials.

Environmental conditions vary according to the geographical areas, and it varies in many countries throughout the year. Polyamides are sensitive to the environmental humidity and can absorb a large amount of moisture from the environment. It becomes necessary to test these materials in their original working conditions, and sometimes it is mandatory to see the effects of extreme environmental conditions on a component. In this article, efforts have been made to investigate the influence of extreme humidity/water conditions on thermo-mechanical properties of PA6/h-BN composites.

This paper aims to investigate the mechanical and thermal behavior, i.e. tensile strength, hardness, impact strength and glass transition temperatures of water-treated polyamide6/boric oxide (PA) composites.

The PA6 and PA6/boric oxide composites were exposed to an open environment and immersed in water for 15 days to analyze the effect of environmental humidity and frequent water immersion conditions on the composite’s mechanical and thermal properties. The tensile strength, elastic modulus, hardness and impact strength of materials were measured to identify the mechanical properties. The scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) characterizations were used to see the effect of humidity/water absorption on microstructure, crystallinity and glass transition temperatures.

The testing results revealed the loss in strength, elastic modulus and hardness, while the impact resistance was improved after exposure of materials to humidity/water. SEM images clearly show the formation of voids and XRD graphs revealed the loss in crystallinity after water immersion. The DSC plots of water immersed materials revealed the loss of glass transition temperatures up to 15°C.

The mechanical and thermal behavior of PA composites varies according to the surrounding atmosphere. Experiments were performed to investigate the influence of water treatment on the PA6/B₂O₃ composite’s mechanical and thermal properties. Water treatment resulted in the bonding between PA and water molecules, which generated voids in the materials. These voids generations are found the main reason for the low strength and hardness of water-treated materials.

This study aims to fabricate and study the effect of five cumulative graphite (G) and graphite nanoplatelets (GNP) filler loading composites by polymerising PA6 precursor; monomer epsilon caprolactam with the two carbons in situ while taking cognisance of the mixing effects (simultaneous stirring and sonication at varying amplitudes and duration). Different aspect ratios will be used to model the two streams of polymerisations.

High viscosity extrusion grade PA6 and synthetic G of less than 2 µm particle size were used as fillers. GNP and G are dried for 6 h in vacuum oven at 90°C. Prior to in situ polymerisation, probe sonication was applied to disperse fillers in molten ɛ-caprolactam, the PA6 monomer. Five carbon loadings were made, that is 5–25 Wt.% for G and 0.5–2.5 Wt.% for GNP composites. Two different sonification regimes were applied 20% sonication amplitude for 20 min (20/20) and 40% sonication amplitude for 10 min (40/10).

Better tensile properties were achieved using the 20/20 processing streams for both G and GNP. The G- and the GNP-based composites systems of the 20/20 processing stream had tensile modulus and yield strength retained or improved above the unfilled PA6 value. The highest modulus obtained in the 20/20 streams are 1,878 and 1,201 MPa, respectively, for GNP and G at the highest loading levels, while the 40/10 processing streams had 963 and 1,247 MPa, respectively, for the GNP and G.

To the best of the authors’ knowledge, nobody has ever used sonification amplitude to compare mechanical properties.

This study aims to highlights the mechanical, thermal and melting behavior compatibility of aluminum (Al)-reinforced polyamide (PA) 6/acrylonitrile butadiene styrene (ABS)-based functional prototypes prepared using fused deposition modeling (FDM) from the friction welding point of view. Previous studies have highlighted the use of metallic/non-metallic fillers in polymer matrix for preparations of mechanically improved FDM feedstock filaments and functional prototypes. But hitherto, very less has been reported on fabrication of functional prototypes which fulfill the compatibility of two polymers for joining/welding-based applications. The compatibility of two dissimilar polymers enables the friction welding for maintenance applications.

The twin screw extrusion process has been used for mechanical mixing of metallic reinforcement in polymer matrix, and final blend of reinforced polymers in the form of extruded feed stock filament has been used on FDM for printing of functional prototypes (for friction welding). The methodology involves melt flow index (MFI) investigations, differential scanning calorimetry (DSC) investigations for thermal properties, tensile and hardness testing for mechanical properties and photo micrographic investigations for metallurgical properties on extruded samples.

It was observed that the reinforced ABS and PA6 polymers have better compatibility in the terms of similar melt flow, thermal properties and can lead to the better joint efficiency with friction welding.

In the present work composite feed stock filament composed of ABS and PA6 with reinforcement of Al powder has been successfully developed for preparation of functional prototype in friction welding applications.

This paper aims to investigate the tribological performance, i.e. abrasion resistance, friction coefficient and wear rates, of self-lubricated water conditioned polyamide6/boric oxide composites.

Polyamide6 and polyamide6/boric oxide self-lubricated composites were immersed in water for 15 days to analyze the effect of water conditioning on friction, wear and abrasion resistance. Tribological testing on pin-on-disc tribometer and abrasion resistance testing on TABER abrader were performed to see the friction coefficient and wear rates of materials. The scanning electron microscopy (SEM) characterizations were performed to analyze the wear tracks.

Tribological testing results revealed the loss in abrasive resistance, but there was an improvement in frictional coefficient and wear rates with steel after water absorption. The SEM images clearly show less depth of wear tracks in water-conditioned materials than dry ones. Water conditioning was found supportive in the formation of smooth lubricating transfer film on steel disc during the tribological testing.

The tribological behaviour of polymer composites is different in dry and in high humidity or water conditions. Experiments were performed to investigate B₂O₃ solid lubricant filler effectiveness on tribological behaviour of water-conditioned polyamide composites. Bonding between polyamide6 and water molecules plus the formation of orthoboric acid was found advantageous in decreasing the friction coefficient and wear rates of composites.

The mechanical and tribological properties of polymers and polymer composites vary with different environmental conditions. This paper aims to review the influence of humidity/water conditions on various polymers and polymer composites' mechanical properties and tribological behaviors.

The influence of humidity and water absorption on mechanical and tribological properties of various polymers, fillers and composites has been discussed in this paper. Tensile strength, modulus, yield strength, impact strength, COF and wear rates of polymer composites are compared for different environmental conditions. The interaction between the water molecules and hydrophobic polymers is also represented.

Pure polymer matrices show somewhat mixed behavior in humid environments. Absorbed moisture generally plasticizes the epoxies and polyamides and lowers the tensile strength, yield strength and modulus. Wear rates of PVC generally decrease in humid environments, while for polyamides, it increases. Fillers like graphite and boron-based compounds exhibit low COF, while MoS2 particulate fillers exhibit higher COF at high humidity and water conditions. The mechanical properties of fiber-reinforced polymer composites tend to decrease as the rate of humidity increases while the wear rates of fiber-reinforced polymer composites show somewhat mixed behavior. Particulate fillers like metals and advanced ceramics reinforced polymer composites exhibit low COF and wear rates as the rate of humidity increases.

The mechanical and tribological properties of polymers and polymer composites vary with the humidity value present in the environment. In dry conditions, wear loss is determined by the hardness of the contacting surfaces, which may not effectively work for high humid environments. The tribological performance of composite constituents, i.e. matrix and fillers in humid environments, defines the overall performance of polymer composite in said environments.