Mechanical Properties Of Polycarbonate Research Articles

Effect of Temperature on Physical and Mechanical Properties of Monolithic Polycarbonate

The study of the physical and mechanical properties of polycarbonate under various temperature conditions, taking into account its widespread use as a base material of monolithic polycarbonate systems in various climatic regions, will ensure a high degree of reliability of structures during operation in a wide temperature range. The authors of the article conducted a series of tensile tests of monolithic polycarbonate in the temperature range from -60 to +80 °C. The influence of temperature on the following characteristics of monolithic polycarbonate was evaluated: elongation at break, tensile yield strength, tensile stress at break, strains at the end of the elastic stage of the material. As a result of the conducted experimental studies, the relationship between the strength properties of monolithic polycarbonate and the operating temperature was revealed. The values of elongation at break at temperatures exceeding 15 °C for various samples generally correspond to the values obtained during tests conducted under standard conditions.

A novel macromolecular phosphorus-nitrogen containing flame retardant for polycarbonate

In this paper, an innovative macromolecular phosphorus-nitrogen containing flame retardant (PDPSB) was successfully designed and synthesized to investigate its impact on the flame retardancy, burning behavior, thermal stability, mechanical properties of polycarbonate (PC) composites. Furthermore, an in-depth exploration of the potential flame-retardant mechanism was conducted. The combustion results indicated that PC-3 with 3 wt% PDPSB reached V-0 rating in UL-94 test and showed a high limiting oxygen index (LOI) of 33.0 %. Compared to pure PC, the values for peak of heat release rate (PHRR), total heat release (THR) and total smoke production (TSP) of PC-3 were decreased by 37.9 %, 11.1 % and 4.9 %, respectively. It was noteworthy that the amount of char residue for PC-3 was raised from 7.4 % for pure PC to 15.8 % with increasing 113.5 %. The thermogravimetric analysis (TGA) results under N2 atmosphere revealed that PDPSB possessed preferable thermal stability with initial decomposition temperature (Tinitial) of 342.6 °C and higher char residue yield of 48.4 %. With increasing the amount of PDPSB, the maximum mass loss rate (Rpeak) was reduced and the char residue yield was increased for PC/PDPSB composites. In addition, the mechanical properties of PC/PDPSB composites were well maintained due to the good compatibility and dispersion between PDPSB and PC matrix. The tensile, flexural and izod impact strength of PC-3 were weakened by 4.3 %, 1.7 % and 16.8 % in comparison of pure PC, respectively. Based on the investigation into the flame-retardant mechanism of PDPSB, the excellent flame retardance of PC/PDPSB composites has been validated. In gaseous, the release of pyrolysis gases was suppressed and active radicals were captured by generated phosphorus free radicals. In condensed phase, the stable char residue with phosphorus and nitrogen elements acted as a barrier to hinder heat, flame and oxygen. This high-efficient single-component multifunctional additive presented a novel approach to the development of fire-resistant polymers with enhanced performance characteristics.

Preparation and Characterization of Antibacterial Polycarbonate (PC) Using High Thermal Resistant Quaternary Fluoroalkyl Phosphonium Salts as Antibacterial Agents

In our previous study, quaternary fluoroalkyl phosphonium salt with iodine anion (PPICF-13) was synthesized as an antibacterial agent for PC, but it would dye PC to be brown during processing because of the oxidation of the iodine. With the aim to eliminate the dyeing problem, three quaternary fluoroalkyl phosphonium salts (PPCF) with trifluoroacetate (TFA-PPCF-13), tetrafluoroborate (FB-PPCF-13), and trifluoromethanesulfonate (TFMS-PPCF-13) were synthesized in the research described here through anion exchange reactions between PPICF-13 with the relative silver salts. After evaluation of their antibacterial activity and thermal stability, FB-PPCF-13 was chosen to prepare antibacterial PC through injection processing. The influence of FB-PPCF-13 concentration on the mechanical properties, thermodynamic properties, light transmittance, appearance, and antibacterial activity of the antibacterial PC was investigated. The results showed that incorporation of FB-PPCF-13 had no negative influence on the mechanical properties of PC, but could reduce Tg and increase the MFI due to the plasticization effect of FB-PPCF-13. When the concentration of FB-PPCF-13 was 2 wt.% or more, the resulting antibacterial PC could have strong antibacterial activity no matter before or after being aged. Though FB-PPCF-13 reduced the light transmittance of PC, it did not influence the color scheme of dyed PC products.

Mechanical Properties and Fracture Microstructure of Polycarbonate under High Strain Rate Tension.

In this paper, static and dynamic tensile tests were conducted on two kinds of polycarbonate (HL6157 and A1225BK), combined with the digital image correlation (DIC), for guiding the development of the battery pack of new energy vehicles. The mechanical properties of polycarbonate at low-speed (0.01/s) and high-speed (1/s, 100/s) tension were investigated and the microstructure of the fracture for polycarbonate at different speed tensions was also investigated. The fracture microstructure of two kinds of materials was also investigated in this paper. The tension results showed that as the strain rate increased, the yield strength and modulus increased, and the yield strength of the two materials increased by 30% under high-speed tension. In addition, the fracture strain increase was greater than 10% as the strain rate increased. Meanwhile, for polycarbonate, the strain rate increased, and the fracture toughness increased.

Characterization of the surface properties and adhesion behavior of electroplated PC/ABS using nano-indentation and scratch tests

The thermal and mechanical properties of Polycarbonate and Acrylonitrile–Butadiene–Styrene (PC/ABS) blends are more and more accepted as substitutes for metals especially in automotive industries. In addition, like metals, PC/ABS can be electroplated, which enhances their application range and gives them an attractive design. This study purported to characterize the surface properties and investigate the adhesion behavior of electroplated PC/ABS parts in order to further facilitate their integration as cheaper and lighter alternative materials. To achieve this goal, we used the measurement of the mechanical properties, a preliminary microstructural study, the scratch and nano-indentation tests to characterize the surface properties of this polymer. This study revealed two main findings. Firstly, the PC/ABS blend had a smooth and compact microstructure with a film of about 13 µm. Secondly, the electroplated film improved the surface mechanical properties of PC/ABS substrate. Finally, the material blend adopted in this study showed a high adhesion quality since the critical loads were LC1 = 6.8 N and LC2 = 11.2 N.

Size and print path effects on mechanical properties of material extrusion 3D printed plastics.

Print conditions for thermoplastics by filament-based material extrusion (MatEx) are commonly optimized to maximize the elastic modulus. However, these optimizations tend to ignore the impact of thermal history that depends on the specimen size and print path selection. Here, we investigate the effect of size print path (raster angle and build orientation) and print sequence on the mechanical properties of polycarbonate (PC) and polypropylene (PP). Examination of parallel and series printing of flat (XY) and stand-on (YZ) orientation of Type V specimens demonstrated that to observe statistical differences in the mechanical response that the interlayer time between printed roads should be approximately 5 s or less. The print time for a single layer in XY orientation is much longer than that for a single layer in YZ orientation, so print sequence only impacts the mechanical response in the YZ orientation. However, the specimen size and raster angle did influence the mechanical properties in XY orientation due to the differences in thermal history associated with intralayer time between adjacent roads. Moreover, all of these effects are significantly larger when printing PC than PP. These differences between PP and PC are mostly attributed to the mechanism of interface consolidation (crystallization vs. glass formation), which changes the requirements for a strong interface between roads (crystals vs. entanglements). These results illustrate how the print times dictated by the print path layout impact observed mechanical properties. This work also demonstrated that the options available in some standards developed for traditional manufacturing will change the quantitative results when applied to 3D printed parts.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40964-022-00275-w.

Photoinduced plasticizing effect of the addition of azobenzene on the glass transition temperature and mechanical properties of polycarbonate

Photoinduced plasticizing effect of the addition of azobenzene on the glass transition temperature and mechanical properties of polycarbonate

The Influence of Environmental Stress Cracking (ESC) and Gamma Irradiation on the Mechanical Properties of Polycarbonate: Study of Synergistic Effects

Polycarbonate is an engineering polymer due its outstanding properties and is widely used in several different applications. In some of these applications it can be exposed to certain liquids/solvents. In many cases, this liquid exposure may cause an effect known as Environmental Stress Cracking (ESC), which may lead to crack formation on the polymer surface and consequent reduction of its mechanical resistance, with loss of lifetime. On the other hand, polycarbonate medical supplies are often exposed to gamma rays in the radio-sterilization process, at doses up to 25 kGy. This exposure causes main chain scissions. In this present work, the viscosity average molecular weight decreased about 10% at 25 kGy. Elongation at break was drastically affected by ESC phenomenon. When simultaneously exposed to the ESC agents (methanol or isopropanol) and gamma radiation, combined effects of both takes place. Moreover, the stress relaxation rate of ~1000 Pa/s (air or methanol) and ~2200 Pa/s (isopropanol) at the dose of 100 kGy, suggests strong influence of isopropanol as surfactant on PC. Results of elongation at break and stress relaxation rate were reliable data to evaluate ESC and radiolytic effects on PC.

Mechanical properties of polycarbonate under intermediate strain rates compression

Mechanical properties of polycarbonate under intermediate strain rates compression

Effects of Steam Heat and Dry Heat Sterilization on Thermal and Mechanical Properties of Nylon and Policarbonate in Fabrication with Fused Filament

In this article presents evidence about performance of mechanical properties of polycarbonate and nylon materials, which are used in the additive manufacturing by deposition of molten material and that have been subjected to sterilization processes by moist heat at 121°C and dry heat at 140°C. This study provides useful information to consider the use of these materials in sanitary and sterile settings. Mechanical tests of tensile, flex, hardness, Izod impact, thermal tests in Differential Scanning Calorimetry DSC, Thermomechanical analysis TMA and Scanning Electron Microscopy SEM were performed. It is concluded that the mechanical and thermal properties have not been altered through the effect of temperature in sterilization processes.

The compatibilizer content effect on tensile and flexural properties of PC/ABS blends

In this research, the effect of styrene-maleic anhydride (SMA), methyl methacrylate-butadiene–styrene (MBS) and maleic anhydride-grafted ABS (ABS-g-MAH) compatibilizer on thermal and mechanical properties of polycarbonate (PC) and poly(acrylonitrile–butadiene–styrene) (ABS) blends were studied. PC/ABS blends samples with varying contents of compatibilizer were prepared. With the compatibilizer content increases, the results indicated that the effects of these three compatibilizers on PC/ABS blends are not exactly the same. When the SMA content increases from 5 to 20wt%, the impact strength reduced by about 76% from 43.24 kJ/m2 to 10.20 kJ/m2. The SEM picture indicated that when SMA content exceeds 5wt%, SMA resin begins to aggregate and leading to inadequate interfacial bonding between SMA and PC/ABS phases. The results showed that about 5wt% of ABS-g-MAH can improve the impact strength of the blends by about 113% and have little effect on the tensile and flexural properties. Similarly, when the MBS content reaches about 5wt%, the impact strength of PC/ABS blends is increased by about 112%, but as the MBS content increases to 20wt%, the tensile and flexural properties reduced by about 25%.

Thermal transfer, interfacial, and mechanical properties of carbon fiber/polycarbonate-CNT composites using infrared thermography

Electrical resistance (ER) and thermogram measurements were used to evaluate thermal transfer, interfacial and mechanical properties of carbon fiber reinforced thermoplastic polycarbonate composites. Carbon nanotubes (CNTs) were fairly uniformly dispersed in polycarbonates using a solvent dispersion method. The CNTs were then further dispersed with an additional time using a twin screw extruder. The effect of CNT on the mechanical properties of polycarbonate was evaluated using a thin film tensile test. For thermogram to evaluate the transferring temperature the composite was placed on a hotplate and copper wires were inserted in the composite at uniform thickness intervals. Due to the different inherent thermal conductivity of CNT, ER was measured to detect thermal changes in the carbon fiber/CNT-polycarbonate composites. The comparison of interlaminar shear strength (ILSS) was to investigate effects of CNT on mechanical and interfacial properties. The uniform distribution of CNTs affected all of these properties in carbon fiber-reinforced thermoplastic composite. Furthermore, heat transfer and heat release become more rapid with the addition of CNT than the without case.

Assessment of the Microstructure and Mechanical Properties of Polycarbonate (PC)/Acrylonitrile Butadiene Rubber (NBR) Blends Reinforced with Multi-wall Carbon Nanotubes

A series of polycarbonate (PC)/acrilonitrile butadiene rubber (NBR)/multi-wall carbon nanotube (MWCNT) nanocomposites were prepared via melt compounding in an internal mixer. The effect of the MWCNT content on the morphology and the thermal and mechanical properties of the prepared nanocomposites were studied. The morphologies of the samples were investigated by field-emission scanning electron microscopy (FESEM) and the thermal properties by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The tensile mechanical results of the nanocomposites showed a decrease in elongation at break with an increase of only 2 wt% of MWCNT content in the PC/NBR blends, and an increasing value in elastic modulus and tensile strength of the nanocomposites. The FESEM images showed that the MWCNTs had good affinity with the polymers and no compatibilizer was needed for making the nanocomposites. The DSC and TGA results showed an increase in thermal stability with addition of MWCNTs because of the more thermally stable carbon nanotubes particles which was uniformly dispersed within the nanocomposites.

Novel Core-Shell Hybrid Nanosphere towards the Mechanical Enhancement and Fire Retardance of Polycarbonate.

It is a huge challenge to achieve highly efficient fire retardance with no mechanical damage to polymers. In our current research, a novel core-shell titanium dioxide@diphenylphosphinic (TiO2@DPP) nanosphere was first synthesized through a hydrothermal reacting process, and applied in simultaneously enhancing the fire retardance and mechanical properties of polycarbonate (PC). The well-designed TiO2@DPP exhibited a significant effect on combustion performance and mechanical reinforcement of PC. At only 0.10 wt % of TiO2@DPP, PC/TiO2@DPP passed the UL-94 V-0 rating, and its oxygen index value rose to 29.3%. Moreover, the peak value of the heat release rate was remarkably decreased by 34.1% in the combustion test, accompanied by the formation of more compacted char layer and the release of more incombustible gas. Equally important another aspect is that the PC containing only 0.10 wt % of TiO2@DPP possessed higher elongation at break and higher tensile strength than pure PC, correspondingly increased by 27.7 and 14.7%. The analysis of the flame-retardant mechanism revealed that the improved fire retardance of PC is primarily ascribed to the barrier action of a cross-linking network containing phosphorus and titanium, the dilution of nonflammable gases such as H2O, and the quenching effect of free radicals which are from the phosphorous group in the gas phase. All these experimental results demonstrate that the core-shell hybrid TiO2@DPP may achieve a simultaneous significant improvement in fire retardance and mechanical properties of PC.

Modulus enhancement of polycarbonate by addition of lithium perchlorate

ABSTRACTThe mechanical properties of polycarbonate (PC) containing lithium perchlorate (LiClO4), which is found to ionize in PC, are examined. The modulus of PC is greatly enhanced by the addition of LiClO4 because of the electrostatic interaction between the lithium cation and the carbonyl group in PC molecules. Previously reported organic antiplasticizers, which fill the free volume of polymers, are known to reduce mechanical toughness and heat resistance. However, the addition of LiClO4 does not sacrifice the advantages of PC, such as heat resistance, transparency, and mechanical toughness. This phenomenon is notable because it is applicable for the enhancement of the mechanical properties of PC. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44882.

Engineering Thermoplastics for Additive Manufacturing: A Critical Perspective with Experimental Evidence to Support Functional Applications.

Among additive manufacturing techniques, the filament-based technique involves what is referred to as fused deposition modeling (FDM). FDM materials are currently limited to a selected number of polymers. The present study focused on investigating the potential of using high-end engineering polymers in FDM. In addition, a critical review of the materials available on the market compared with those studied here was completed. Different engineering thermoplastics, ranging from industrial grade polycarbonates to novel polyetheretherketones (PEEKs), were processed by FDM. Prior to this, for innovative filaments based on PEEK, extrusion processing was carried out. Mechanical properties (i.e., tensile and flexural) were investigated for each extruded material. An industrial-type FDM machine (Stratasys Fortus® 400 mc) was used to fully characterize the effect of printing parameters on the mechanical properties of polycarbonate. The obtained properties were compared with samples obtained by injection molding. Finally, FDM samples made of PEEK were also characterized and compared with those obtained by injection molding. The effect of raster to raster air gap and raster angle on tensile and flexural properties of printed PC was evidenced; the potential of PEEK filaments, as novel FDM material, was highlighted in comparison to state of the art materials. Comparison with injection molded parts allowed to better understand FDM potential for functional applications. The study discussed pros and cons of the different materials. Finally, the development of novel PEEK filaments achieved important results offering a novel solution to the market when high mechanical and thermal properties are required.

Effect of Pigment Concentration on Mechanical Properties of Polycarbonate

This experimental study deals with the influence of pigments on the mechanical properties of polymeric polycarbonate material Lexan 923c, which is commonly used in industry and is being processed with injection technology. This material was stained with three different pigments from Lifokolor. It was also stained with 6 different concentrations of selected pigments. Emphasis was placed on measuring the tensile strength, impact strength and hardness of polyurethane mixtures.

Electrically conductive polycarbonate/ethylene‐propylene copolymer/multi‐walled carbon nanotubes nanocomposites with improved mechanical properties

ABSTRACTIn this article, the effect of Multi‐walled carbon nanotubes (MWCNTs) on the electrical conductivity and mechanical properties of polycarbonate (PC) toughened with cross‐linked ethylene‐propylene copolymer (EPC) was investigated. The solubility parameters of the PC and EPC were calculated using Hoy methods to clarify the miscibility of the polymer blends. It could be concluded that in the cooled state, the blends form a heterogeneous structure with two separate phases. The tensile, flexural, impact toughness properties of the PC/EPC blend and PC/EPC/MWCNT nanocomposites were carried out to illuminate the optimum concentration of polymer blends and MWCNTs. The 335% increment for the impact strength results appeared with combination of 10% EPC in the PC matrix. The flexural modulus and strength of PC/EPC blend increased by 75.1% and 59.1%, respectively. The Nielsen model was performed to fit the best curve of theoretical simulation to experimental results for elastomeric dispersed in the plastic matrix. Halpin‐Tsai model was applied to estimate the stiffness of nanocomposites blends with different volume fraction and aspect ratio of MWCNTs in the PC/EPC blends. Finally, in the presence of MWCNTs, all nanocomposite samples were semi‐conducting and the percolation threshold of the PC/EPC (10%) blends was between 0.5% and 1.0% MWCNTs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44661.

Polycarbonate composites: Effect of filler type and melt‐blending process on the light diffusion properties

Transmittance and haze are key properties of light diffusion materials. Hybrid light diffusion agents (LDAs) and melt‐blending process are introduced to study optical performance and mechanical properties of polycarbonate (PC) light diffusion materials. Optical properties of PC composites prepared by two‐step melt‐blending process has better repeatability compared to one‐step method due to the better dispersion state of hybrid fillers in PC matrix. The hybrid fillers silicate microspheres (SMS)/nano titania particles (nTiO2) are more suitable for PC matrix compared to cross‐linked poly(methyl methacrylate) microspheres (PMMA)/nTiO2, for the reason that the PC/SMS/nTiO2 composites exhibit favorable optical performance and almost no deterioration of mechanical properties. The good balance between high transmittance and substantial haze can be achieved when the SMS/nTiO2 content is 1.2 wt% (the transmittance and haze are 60.97% and 88.73%, respectively). POLYM. ENG. SCI., 57:374–380, 2017. © 2016 Society of Plastics Engineers

Synthesis of tris(phenoxy)trifluorocyclotriphosphazenes and study of its effects on the flammable, thermal, optical, and mechanical properties of bisphenol-A polycarbonate

A flame-retardant tris(phenoxy)trifluorocyclotriphosphazenes, 2,4,6-N3P3(OPh)3F3 (TCTP) containing phenoxyl, fluorine, and cyclotriphosphazene ring was synthesized from hexachlorocyclotriphosphazene and added to polycarbonate (PC) to improve flame retardancy. Its chemical structure was confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance. The synthesis of TCTP was designed to improve the flame retardancy of PC without harming PC excellent optical and mechanical performances. The flame retardancy and thermal degradation behavior of PC/TCTP composites were investigated with the limiting oxygen index (LOI), UL-94 vertical burning test, microscale combustion calorimeter, thermogravimetric analysis, and differential scanning calorimetry. Scanning electron microscopy (SEM) analyses and FTIR spectrophotometer were brought together to study the structure of residual char. The optical and mechanical properties of PC were also taken into consideration at the same time. When 10 % TCTP was incorporated, the LOI of composite achieved the maximum of 40 %, and class V-0 of UL-94 test was passed. The phenomena of SEM and FTIR stated that there was interaction between PC and TCTP to form new stable film in mid of residual char. Light transmittance, tensile, and flexural strength of PC/TCTP systems were improved at different levels.