Society Of Plastics Engineers Research Articles

Retraction Statement: A novel composite coating to improve the environmental adaptability of combustible cartridges

The above article from Polymer Composites, published online January 4, 2018 and corrected January 11, 2018 in Wiley Online Library (wileyonlinelibrary.com), has been retracted as agreed by the authors, the Journal’s Executive Editor, Sadhan Jana, the Society of Plastics Engineers, and Wiley Periodicals, Inc. The retraction has been agreed after the authors repeated their analysis, finding the early studies to be non‐reproducible.ReferenceChen, S. and Yu, W. (2019), A novel composite coating to improve the environmental adaptability of combustible cartridges. Polym. Compos., 40:695‐703. https://doi.org/10.1002/pc.24721

May 2020 Editorial in PES

May 2020 Editorial in <scp>PES</scp>

SPE Thermoforming Division Announces Winners of Annual Parts Competition

The Society of Plastics Engineers (SPE) Thermoforming Division has announced the winners of its annual parts competition.

Sustainability, New and Improved Materials a Big Part of 13th SPE AutoEPCON

The Society of Plastics Engineers (SPE) hosted the Automotive Engineering Plastics Conference (AutoEPCON) in the Motor City suburbs for the 13th time between April 30 and May 1. The event, organized by SPE's Detroit Section and Automotive and Injection Molding Divisions, proved that there is still much interest in the world of engineering thermoplastics and that manufacturers continue to invest in and innovate around this technology segment. Several products made their world or North American debut, and many other grades of recently introduced, higher‐performance engineering thermoplastics were highlighted in technical talks and at displays.

Utilization of side streams from paper industry as fillers in polypropylene composites

Sustainable, low‐cost composite materials with improved performance typically contain, in addition to plastics, mineral fillers and fibers. Similar composite materials can also be produced by replacing fillers and fibers with side streams from paper mills using paper for recycling as their raw material. These side streams can be of different qualities and thus various end uses exist. The strength and water adsorption properties of such composites provide many opportunities for their application. Further, their environmental benefits are clear, since the use of these side streams reduces the need to landfill them. The study was also supported by chemical analysis of the side streams. This approach can also bring in additional revenue from the same raw material stream, improving overall resource and economic efficiency. POLYM. COMPOS., 39:4000–4009, 2018. © 2017 Society of Plastics Engineers

Predicting thermal degradation mechanisms in urea–formaldehyde cellulose composites filled with tin particles

This article reports a study on structural characterization, thermal stability, and prediction of the thermal degradation mechanisms of urea–formaldehyde cellulose (UFC) composites filled with tin particles by condensed phase kinetic approaches. Structural characterization of UFC/Sn composites performed by scanning electron microscopy, X‐ray diffraction, and Fourier‐transform infrared analyses demonstrates that the composites are fairly homogenous, and the interactions between UFC and tin in the composites are physical in nature. Measurements of inherent thermal stabilities, apparent reaction profiles, and thermal degradation kinetics of UFC and UFC/Sn composites have been carried out on the thermoanalytical data of materials. The integral procedure decompositions temperature elucidates the increasing thermal stabilities trend of UFC/Sn composites with the increase in tin contents in UFC matrix. Reaction profiles of UFC and UFC/Sn composites suggest considerably complex thermal degradation pathways of the materials which comprise various competitive/consecutive reactions. Substantial variations in the activation energies of matrix and composites with the advancement of reaction by generalized integral isoconversional method verify their multistep reaction mechanisms. Advanced reaction model determination methodology with the help of a novel kinetic function F(α, T) reveals that the multistep thermal degradation of UFC goes to completion by overall following intricate nucleation/growth mechanisms. A detailed account of the mechanistic information related to thermal degradation of UFC and UFC/Sn composites is also given and discussed in this study. POLYM. COMPOS., 39:4341–4354, 2018. © 2017 Society of Plastics Engineers

Effect of addition of organomodified montmorillonite nanoclay on three-body abrasive wear behavior of maleic anhydride grafted polyethylene compatibilized ethylene-co-vinyl acetate/high density polyethylene nanocomposites

In this experimental study, effect of addition of organomodified montmorillonite (OMMT) nanoclay in increasing quantity, viz. 0, 1, 2, 3, and 4 parts per hundred on three-body abrasive wear behavior of maleic anhydride grafted polyethylene compatibilized ethylene-co-vinyl acetate/high-density polyethylene (EVA/HDPE/MA-g-PE) nanocomposites have been investigated. Experiments were conducted on rubber wheel abrasion tester, which was in-house developed according to ASTM G65-04 standard. Comparative wear volume loss and specific wear rate of polymer nanocomposites were evaluated at different loads and sliding distances with 300 µm sand abrasive size particles. It was observed that both wear volume loss and specific wear rate were increased with increase in loads. Wear volume loss was increased with increase in sliding distance while specific wear rate was decreased. Taguchi (L18) design of experiment and analysis of variance were used to optimize control factors and determine statistical significance and percentage contribution of control factors. Scanning electron microscopic images showed surface fatigue and microploughing wear mechanism on surface matrix. The aim of this study is to establish the prospects of studied polymer nanocomposites in automobile, aerospace, and similar industrial applications, where three-body abrasive wear is dominating. POLYM. COMPOS., 2017. © 2017 Society of Plastics Engineers

Effects of cure-hold-temperature and step-wise cool-down path on the service strength of fiber-mat reinforced composites

The study considered the influence of the cure hold temperature and the techniques applied in cooling to room temperature on the strength of random fiber reinforced thermoset composites. Tensile and Charpy impact tests were carried-out on chopped strand mat E-glass fiber reinforced-polyester composites cured at temperatures ranging between 30°C and 150°C and subsequently cooled through different paths. The composites contained 3 plies for the tensile test specimens, and 10 plies for the Charpy impact test specimens. The matrix was prepared from the same bulk and formulation. From the tests, samples oven cured at 85°C/3 hr and cooled under natural convection cool-down path were found to give the highest tensile strength of 96 MPa while the laminate cured at 30°C room temperature produced the lowest strength of 69 MPa. Also, samples cured at 85°C under natural convection cooling gave an average impact strength value of 550 kJ/m2, which is second to fridge cooled samples of 650 kJ/m2 average value. There is therefore need for oven-cure followed by quenching to obtain maximum strength in polyester laminate applications. POLYM. COMPOS., 2017. © 2017 Society of Plastics Engineers

Influence of graphene oxide on thermal, electrical, and morphological properties of new achiral polyimide

In this study, a new diamine N‐[2‐(1H‐indol‐3‐yl)ethyl]‐3,5‐diaminobenzamide (IEDAB) was synthesized using tryptamine as starting material and characterized by FT‐IR, 1H‐NMR, 13C‐NMR, and mass spectroscopy. Then, it was polymerized with 3,3',4,4'‐benzophenone tetracarboxylic dianhydride (BTDA) via thermal imidization to produce polyimide (PI). A series PI/GO nanocomposite films were prepared by incorporating different ratios (1, 3, and 5 wt%) of synthesized GO by solution casting method. The synthesized PI was confirmed by Ubbelohde viscometer and FT‐IR spectroscopy. SEM and Raman spectroscopy showed that GO was well dispersed in the PI matrix. XRD patterns indicated the PI and PI/GO nanocomposite films were highly amorphous in nature. The synthesized PI and their nanocomposites show high thermal stability as their T10% weight loss are in the range of 498 to 563°C with 30.6 to 40% of char yield and the glass transition temperatures (Tg s) are in the range of 188 to 262°C. The limited oxygen index (LOI) values increased from 31.4% to 56.0% with increases of 5% GO content in the PI/GO nanocomposite. They have high dielectric constant in the range of 2.6 to 5.1 at 1 MHz and also good mechanical properties with tensile strength of 81 to 116 MPa, elongation at break 5 to 9%. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers

Preparation and characterization of eucalyptus wood flour/polypropylene composites by subcritical ethanol and 3‐Aminopropyltriethoxysilane as cosolvent

Subcritical fluids assisted reactive extrusion is a novel and promising alternative technique for preparation of wood plastic composites. Because subcritical fluids have moderate process condition, well swollen performance, and excellent dissolvability. Therefore, subcritical fluids are led into the extruder system to alleviate the thermal degradation of wood flour, to reduce the melt viscosity of matrix, and to strengthen the mass transport. The wood flour is expanded in the presence of subcritical ethanol, which favors the permeability. Fourier transform infrared spectroscopy confirms that maleic anhydride grafted polypropylene (PP‐g‐MA) is grafted onto cellulosic chain, and subcritical ethanol promotes the grafting and swollen reaction. A possible mechanism is proposed to explain the effect of subcritical ethanol on the interfacial reactions. In addition, the thermal stability of wood flour, PP, and wood flour/PP composites are studied. Fracture morphology is observed to confirm the interfacial adhesion of wood flour/PP composites. The results suggest that subcritical ethanol leads to a change of crystalline structure of cellulose via X‐ray diffraction. Moreover, the mechanical properties of wood flour/PP composites increase dramatically, while 3‐Aminopropyltriethoxysilane (KH550) is used as co‐solvent dissolving in ethanol. Experimental results reveal that wood flour/PP composites in the presence of subcritical ethanol with 2% KH550 (190°C, 2.4 MPa, and 120 r/min), whose tensile strength, flexural strength, flexural modulus, and non‐notched impact strength increase by 45, 56, 29, and 36%, respectively, possess the best physical properties comparing to those during extrusion without fluids. POLYM. COMPOS., 39:3594–3604, 2018. © 2017 Society of Plastics Engineers

Composite material based on fluoroplast and low melting oxyfluoride glass

The results of studies of the samples fabricated through extrusion blending of mixtures composed of the polymer polyvinylidene fluoride and the inorganic glass of 3B2O3‐97(40SnF2‐30SnO‐30P2O5) are summarized. The composite material whose structure depends on the component ratio in the mixture (from individual areas formed by each component to homogeneously distributed composite particles) has been fabricated. The peculiarities of formation of composites were studied based on the study of their morphology, molecular structure and phase composition. The organic and inorganic components do not interact with each other at the molecular level. The glass crystallizes during formation of the composite. With the increasing amount of crystals, the monolithic polymer is broken; at a certain ratio of the components, there is inversion: the polymer particles are arranged between the crystals of inorganic component, mixing with them, and covering them. The temperature of composite melting is determined by polymer melting. POLYM. ENG. SCI., 57:566–569, 2017. © 2017 Society of Plastics Engineers

Exploring the influence of co-monomer content in the dry crosslinked ethylene octene copolymer based blends

This article illustrates the influence of co-monomer content in the ethylene octene copolymer (EOC) on the dry curing process of EOC:PDMS rubber blends. The EOC:PDMS blends were prepared by melt mixing in an internal mixer and crosslinked through electron beam radiation method. During electron beam irradiation both the EOC and PDMS phase gets crosslinked; which is evident from the gel content study. From the rheology analysis, it is understood that the EOC with high octene (co-monomer) content has better radiation crosslinkability as compared with the EOC with low co-monomer content. Through radiation crosslinking, the physico-mechanical properties of the EOC:PDMS system was improved significantly. The tensile strength of high co-monomer content EOC:PDMS 70:30 blends were drastically improved by 49.5% on irradiation with a dosage of 75 kGy. Morphology study of the EOC:PDMS system were carried out by scanning electron microscopy (SEM) and correlated with the physico-mechanical properties. The radiation crosslinked blends shows higher volume resistivity, lower dielectric constant, and loss as compared with the uncrosslinked counterparts. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Preparation of porous poly(L-lactic acid)-co -(trimethylene-carbonate) structures using supercritical CO2 as antisolvent and as foaming agent

In this work, porous structures of poly(L-lactic acid)-co-(tri-methylene-carbonate) (PLLA-co-TMC) were successfully fabricated using two experimental methods, that is, using supercritical CO2 as antisolvent and as foaming agent through the pressure induced phase separation technique. Considering the phase inversion method, the effect of the initial polymer concentration of the solution, pressure, and temperature on the morphology of the final porous structure (pore size, porosity, and cell density) was investigated. The L–L demixing process was suggested as the dominant mechanism for the phase separation and pore production. The temperature window, for which PLLA-co-TMC porous structures are successfully produced using the pressure induced phase separation technique, was determined at 150 and 210 bar. The effect of temperature on the final porous structure was investigated. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Thermomechanical properties and bioactivity evaluation of silicone rubber composites

The effect of incorporation of nanofillers (montmorillonite, silica, hydroxyapatite) and bioactive glass (BG) microparticles into a silicone elastomer matrix, on its thermomechanical properties and bioactivity was investigated. The obtained samples were characterized using differential scanning calorimetry and dynamic mechanical analysis, as well as by hardness, tensile, and tear testing, whereas their bioactivity was evaluated by immersion of specimens into simulated body fluid solution and by cell culture experiments (fibroblasts and osteoblasts). Montmorillonites and especially Cloisite 20A have been shown the most efficient reinforcement for improving mechanical properties of silicone rubber composites. On the other hand, BG and silica hybrids exhibited significant bioactive properties. POLYM. COMPOS., 39:2560–2570, 2018. © 2016 Society of Plastics Engineers

Fabrication of crystalline articles of aromatic polycarbonate by hot powder-compaction

Polycarbonate is well known for forming amorphous, transparent, and exceptionally tough articles by conventional methods such as injection molding and extrusion. It is not possible to extrude polycarbonate from the melt into crystalline, shaped articles. A novel method to fabricate crystalline polycarbonate articles from acetone-crystallized powder was devised. The method was adapted from powder metallurgy and it involved compacting acetone-crystallized polycarbonate powder above the glass transition temperature (Tg) and below the melting peak temperature (Tm). The hot powder-compaction process yielded shaped articles, which retained the crystallinity of the original polycarbonate powder. Although the crystallinity of the powder and the articles was less than 20%, surprisingly the articles were non-sticking above the Tg and so could be released from the mold at the compaction temperature. Furthermore, the crystalline polycarbonate articles had a Vicat softening temperature above 180°C, excellent shape and dimension retention above Tg, increased hardness, as well as resistance to acetone and other solvents. That is, the properties were different from those of conventional amorphous polycarbonate articles. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Rapid structural changes that take place during constrained annealing of biaxially stretched pet films

The aim of this work is to study the structural changes that take place during the heat setting of simultaneously and sequentially biaxially stretched polyethylene terephthalate films. The rate of structural rearrangement, as detected by real-time birefringence and off-line the Raman spectroscopy, DSC thermal analysis and X-rays, was found to be dependent on the state of the orientation and crystallinity attained by the samples during the stretching step. This suggested that the annealing behavior can be categorized into three regimes according to the birefringence behavior of the samples. At low deformations, the films not crystallized by strain exhibit complete birefringence relaxation without showing any sign of crystallization. The intermediate ratio samples that were stretched to the onset of the strain-induced crystallization exhibited the highest levels of birefringence increase after a short relaxation. The samples stretched well above the onset of the strain-induced crystallization exhibited intermediate level of birefringence and crystallinity increase. Therefore, the classification of the three regimes was found to be related to the onset of the strain-induced crystallization during the stretching step. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Preparation of PLLA/PBAT-strengthened degradable expanded polystyrene

To enhance the flexural strength of degradable expanded polystyrene (DEPS) while maintaining degradability, during the manufacturing processes of DEPS, cerium(III) stearate (CeSt3) and poly-L-lactide (PLLA)/poly(butylene adipate-co-terephthalate) (PBAT) are used as a nontoxic oxidizer and a co-biodegradable polymer filler, respectively. The flexural strength of DEPS is decreased by the oxidizer and increased by the biodegradable polymers. Furthermore, by favorable interfacial interaction between PLLA and PBAT, the flexural strength is more enhanced when the two biodegradable polymers are used simultaneously than used separately. The photo-, bio- and oxo-degradation behaviors of DEPS were evaluated by UV irradiation, thermal treatments, landfill, and non-landfill tests. Molecular weight of our DEPS is decreased to 90.26% after 2 weeks of UV irradiation and 74.4% after 3 months of thermal treatment test. 35.4 and 31.4% of weight of our DEPS is reduced after 3 months of landfill and non-landfill test. It is confirmed that the decomposition period of DEPS could be adjusted by controlling the amount of the oxidizer and/or the biodegradable polymers. The FT-IR study demonstrated that oligomers and nonylphenol which are known to cause the environmental hazards are not generated after the degradation of DEPS. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Molecular motifs for additives that retard PEO crystallization

We investigate the influence of several bifunctional phenol additives (resorcinol: RES, hydroquinone: HYD, p-hydroxybenzoic acid: PHBA, and p-nitrophenol: PNP) on the crystallization of matrix polymer, polyethyleneoxide. We employ solid state Nuclear Magnetic Resonance spectroscopy (NMR), Differential Scanning Calorimetry (DSC), optical microscopy, and Small Angle X-ray Scattering (SAXS) to investigate crystallization of the additivated PEO and compare with Density Functional Theory (DFT) calculations of additive-PEO interactions. Additive-polymer interactions are a function of the functional groups on the additive. Temperature-dependent spherulitic growth rate measurements from optical microscopy and SAXS lamellar long spacings indicate a distinct trend in the effect of additives on PEO crystallization. Change in PEO crystallization is most pronounced with PNP, followed by PHBA and finally RES and HYD. This trend correlates qualitatively with the binding energies of additive-PEO interactions from DFT studies. Our results suggest that DFT calculations might be a useful screening tool to evaluate the influence of additives on polymer crystallization. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers

Magnetic (ethylene-octene) elastomer composites obtained by extrusion

Most research on magnetorheological elastomer (MRE) composites is focused on achieving the best magnetic and magnetorheological properties of composites. Less attention is paid to obtain adequate strength properties. The aim of this study was to receive MRE composites with the best mechanical characteristics. Thermoplastic ethylene–octene rubber composites, filled with different magnetoactive particles were reported. The use of extrusion method instead of traditional preparation processes (two-roll mill, mixer) of composites was also presented. Ferromagnetics: micro- and nano-sized iron oxides, as well as gamma iron oxide and carbonyl iron powder were found to be an active fillers improving both mechanical and magnetic properties of rubber. Application of extrusion process affected mechanical properties of MRE composites and the dispersion of magnetic fillers. Dynamic mechanical analysis (DMA) indicates the presence of strongly developed secondary structure in vulcanizates. Studies investigated by vibration sample magnetometer (VSM) proved that all composites exhibit adequate magnetic properties, predispose them for plenty of applications with the most promising being nowadays tunable vibration absorbers. POLYM. ENG. SCI., 57:520–527, 2017. © 2016 Society of Plastics Engineers

Properties of flocs in sludge conditioning by a novel amphoteric polymer with different anionic degrees

This paper aimed to examine how the amphoteric conditioner poly (acrylamide-′acryloyloxyethyl trimethyl ammonium chloride −2-acrylamido-2-methyl-propane sulfonate) (PADA) with different anionic degrees (AD) affected the properties of sludge flocs in the conditioning. The floc properties were characterized by morphological parameters (floc size distribution, fractal dimension, specific surface area, and pore volume), physical properties (floc strength and surface charge density), and chemical constituents (Fe3+, Al3+ and extracellular polymeric substances (EPS), including the polymeric proteins and carbohydrates). The results of this investigation revealed that (1) morphological properties of flocs were associated with anionic degree, particularly in the range of 0–4%, where the anionic degree led to a shift of the particle size toward groupings of larger diameter, meanwhile better regularity and increased compactness of floc structure formed. (2) The introduction of the anionic groups indeed had bad effects on flocs in terms of its stability and charge neutralization, but the downtrend could be inhibited by adjusting the anionic degree of polymer to a reasonable level. (3) The dissolved EPS for sludge followed a role of decreasing firstly then increasing with increased anionic degree, but the content of bound EPS kept nearly constant. (4) The polymer with anionic groups had apparent effects on enrichment of metal ions. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers