Blends of high‐density polyethylene with chlorinated polyethylene: Morphology,thermal, rheological,and mechanical properties

Blends of high‐density polyethylene (HDPE) with chlorinated polyethylene (CPE) were generated using melt mixing. CPE of two different chlorination contents was used and its amount in the blends was varied from 1% till 30%. The rheological, thermal, mechanical, and morphological properties of the blends were characterized along with miscibility analysis. In general, better mixing of the CPE polymer in HDPE was observed at lower CPE concentration and reduced mixing or immiscibility occurred at higher concentration of CPE. However, the extent of immiscibility was different in both CPE25 and CPE35 systems. The rheological analysis of the data using Cole‐Cole, Han‐Chuang and van Gurp plots confirmed the miscibility of CPE25 blends (except for 30% CPE25 blend at lower frequency) whereas CPE35 blends with 10–30% CPE content were immiscible. Highest increase in the rheological properties (complex moduli) was observed at 2% CPE content. The mechanical properties of the CPE25 blends were superior than the corresponding CPE35 blends especially at higher CPE concentration where effects of immiscibility as well as matrix plasticization played a role. The morphology characterization using TEM indicated change in the crystalline features of the polymer in the case of CPE35 blends. The optical microscopy also confirmed the better mixing of CPE25 polymers in HDPE than CPE35. The CPE25 blends exhibited uniformly dispersed CPE phase which was also confirmed by the rheological analysis. However, the blends of CPE35 with 10% CPE content onwards had significant phase immiscibility. POLYM. ENG. SCI., 54:85–95, 2014. © 2013 Society of Plastics Engineers     

The preparation and some properties of chlorinated tung oil

Summary The chlorination of tung oil was investigated, and certain chlorinated products were screened as plasticizers for polyvinyl chloride resin. Chlorine readily added at low temperatures (0 to 20°C.) as well as at higher temperature (75°C.). The chlorination was highly selective for triene conjugation as the disappearance of triene closely paralleled the amount of chlorine added during early staged to chlorination. Considerable conjugated diene is formed as indicated by characteristic ultraviolet absorption in the diene region. In later stages of chlorination considerable substitution occurs as evidenced by the fact that products containing more than 40% of chlorine could readily be obtained. All the products were more or less unstable, evolving hydrogen chloride and darkening at room temperature. The chlorinated tung oils were screened as plasticizers, at the 30% level, for polyvinyl chloride by using butyl epoxystearate as a stabilizer. Products containing small proportions of chlorine (less than about 20%) were not compatible with polyvinyl chloride; products containing moderate amounts (about 30%) were compatible and had some plasticizing effect but decomposed excessively on milling. Those products containing the highest proportion of chlorine (more than 40%) were compatible and did not decompose on milling or molding. These highly chlronated tung oilslowered the milling temperature of polyvinyl chloride copolymer but showed little, if any, ability to product compositions which are flexible at room temperature. Presented at the 32nd Annual Fall Meeting, American Oil Chemists' Society, Chicago, Ill., October 20–22, 1958. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

Mechanical properties,oil resistance,and thermal aging properties in chlorinated polyethylene/natural rubber blends

The use of natural rubber (NR) for partly substituting elastomeric chlorinated polyethylene (CPE) was determined. Mechanical and thermal aging properties as well as oil resistance of the blends were also investigated. The amount of NR in blends significantly affected the properties of the blends. The blends with NR content up to 50 wt % possessed similar tensile strength to that of pure CPE even after oil immersion or thermal aging. Modulus and hardness of the blends appeared to decrease progressively with increasing NR content. These properties also decreased in blends after thermal aging. After oil immersion, hardness decreased significantly for the blends with high NR content, whereas no change in modulus was observed. The dynamic mechanical properties were determined by dynamic mechanical thermal analysis. NR and CPE showed damping peaks at about ?40 and 4 °c, respectively; these values correlate with the glass‐transition temperatures (T_g) of NR and CPE, respectively. The shift in the T_g values was observed after blending, suggesting an interfacial interaction between the two phases probably caused by the co‐vulcanization in CPE/NR blends. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 22–28, 2002; DOI 10.1002/app.10171     

Dielectric,mechanical and thermal properties of some chlorinated poly (p-phenylene oxide)s in the solid state

The dielectric, mechanical and thermal properties were investigated for poly(2,6-dichloro-1,4-phenylene oxide) (PDCPO), poly(2-chloro-6-methyl-1,4-phenylene oxide) (PCMPO) and poly(2,6-dimethyl-1,4-phenylene oxide) (PDMPO). PDCPO exhibited two dielectric secondary relaxations designated as β and γ processes around 160 and 100K, respectively. The γ process was assigned to the motion of a trace of chloroform included in the PDCPO film. A blend film PDMPO/PCMPO ($\text{9}\text{1}$ mixing ratio) exhibited dielectric relaxation around 330K and the process was assigned to the rotation of phenyl group with respect to oxygen-phenyl-oxygen axis. No dielectric relaxation was observed for the PDMPO film dried carefully, while the PDMPO film kept under an atmosphere of water vapour exhibited dielectric relaxation due to the motion of the water molecules at about 180K. Tensile stress at break measured on PDCPO prepared by Stamatoff's method was 38 MPa and was much higher than that for PDCPO prepared by the method reported by Blanchard et al. Temperature dependence of the dynamic Young's modulus for PDCPO measured at 110 Hz exhibited no appreciable loss peak in the range below 480K. Glass transition temperatures for PDCPO, PCMPO and PDMPO were determined to be 490, 445 and 500K, respectively, by differential scanning calorimetry.     

Mechanical,morphological, and thermal properties of (thermoplastic polyurethane)/(chlorinated polyethylene) blends

The preparation and characterization of CPE (chlorinated polyethylene)/TPU (thermoplastic polyurethane) blends with various ratios were investigated. The compatibility, morphology, and rheology, as well as the thermal and physico‐mechanical properties, were studied by differential scanning calorimetry, Fourier‐transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, universal tensile machine analysis, and capillary rheometry. The results showed that CPE is partially miscible with TPU. The introduction of CPE into TPU resulted in a reduction of the viscosity, tensile strength, tear strength, compression set, abrasion resistance, and hardness, whereas the elongation at break was increased. Thermogravimetric analysis showed that the blends underwent two stages of thermal degradation. J. VINYL ADDIT. TECHNOL., 19:192‐197, 2013. © 2013 Society of Plastics Engineers     

Compatibility study of chlorinated polyethylene/ethylene methacrylate copolymer blends using thermal,mechanical, and chemical analysis

Blends of chlorinated polyethylene (CPE) elastomer and ethylene methacrylate copolymer (EMA) in various compositions were studied for their compatibility using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and Fourier transform infrared (FTIR) spectroscopy techniques. Irrespective of measurement techniques used, all blends showed a single glass transition temperature (T_g) lying in between the T_g of control polymers in both DSC and DMA. Glass transition temperatures of blends obtained from DSC were in consistency with Couchman–Karasz equation. Also, the T_g obtained from both DSC and DMA are above the “rule of mixing” line of the two control polymers. These results from thermal analysis clearly indicate some compatibility between the two polymers. Furthermore, compatibility of CPE/EMA blends were also been investigated by FTIR spectroscopy and scanning electron microscopic analysis. A shifting of characteristic C? Cl stretching peak of CPE and C?O stretching peak of EMA toward lower wave number indicate the presence of specific interaction between the two polymers. Mechanical properties like tensile strength, modulus at 100% elongation, elongation at break, and hardness were observed above the line of additivity drawn between the two control polymers, which corroborate compatibility between CPE and EMA. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40316.     

Effect of starch on thermal,mechanical, and barrier properties of low density polyethylene film

Low‐density polyethylene (LDPE) with different quantities of starch was compounded using a twin screw extruder and blown into films by a Konar K, blow‐film machine. Mechanical properties, namely percent elongation, tensile, bursting, and tear strength, as well as barrier properties, such as water vapor and oxygen transmission rate, of the filled LDPE film were studied. Thermal properties of the films were studied using DSC and DMA. Master curves at reference temperature of 30°C were obtained using software linked to DMA. Incorporation of 1% starch in LDPE has marginally affected the thermal, barrier, and mechanical properties; however, that of 5% starch filled LDPE has affected the properties to a great extent. The mechanical properties, such as percent elongation, tensile, tear, bursting, and seal strength, decreased by 19.2, 33.6, 3.60, 10.8, and 22.12%, respectively. Similarly, water vapor and oxygen transmission rate increased to 32.5 and 18.3%, respectively. Other physical properties, namely migration and thermal properties, were also affected in 5% starch filled LDPE; however, the film can still be used as packaging material. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3355–3364, 2006     

Combined effect of isophthalic acid and polyethylene glycol in polyethylene terephthalate polymer on thermal,mechanical, and gas transport properties

The objective of this article is to study the combined effect of isophthalic acid (IPA) and polyethylene glycol (PEG‐400) in PET polymer and film on thermal, mechanical, and gas transport properties. The purpose of developing this material is to reduce the melting point, improve mechanical, thermal, and gas barrier properties. The chosen raw materials, namely, IPA and PEG for copolyester synthesis will replace partially the acid and diol monomers of PET. The molar concentration of comonomers (IPA and PEG‐400) were varied from 2 to 50% and the result shows that the gas barrier properties (namely O₂, CO₂, N₂, and water vapor transmission rate), mechanical, and thermal properties were lesser than that of PET polymer. On improving the crystallinity of PET‐isophthalate‐PEG (PET‐IP) copolymer, barrier properties are improved than that of PET polymer. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Morphological,mechanical, tribological,and thermal expansion properties of organoclay reinforced polyethylene composites

The morphological, mechanical, thermal, and tribological properties of high‐density polyethylene (HDPE) composites reinforced with organo‐modified nanoclay (3 and 6 wt%) were studied. A commercial maleic anhydride‐based polymeric compatibilizer (PEgMA) was used to improve the adhesion between the polyethylene and clay. Transmission electron microscopy (TEM) characterization of composites revealed that nanoclay exists mainly in a multilayered structure in the HDPE matrix. Mechanical testing of composites showed that Young's modulus and tensile strength increased with nanoclay content. Coefficients of the linear thermal expansion (CLTE) of HDPE–PEgMA–clay composites were slightly lower in the flow direction than those of HDPE–PEgMA. The tribological properties were measured in dry conditions against a steel counterface. The friction coefficient of the matrix was decreased by the addition of clay. Electron microscopic results suggested that the wear mechanism for HDPE and HDPE composites was mainly adhesive. Clay agglomerates were observed on the worn surfaces of the composites, which may partly explain decreased friction. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers     

Graphene/polyethylene terephthalate nanocomposites with enhanced mechanical and thermal properties

Nanocomposites made of poly(ethylene terephthalate) (PET) and graphene nanoplatelets (GNPs) were fabricated through micro-compounding and micro-injection molding. With an objective of improving the interactions between GNP sheets and PET chains, PET pellets were ground into a fine powder. PET pellets and powders were mixed with GNPs at 2%, 5%, 7.5%, and 10% (wt.%), molded to fabricate the nanocomposites, and then tested using several analytical characterization tools. Mechanical testing showed greater improvement through powder mixing, resulting in a 58% increase in the elastic modulus of the nanocomposites at 10% weight fraction. Thermal behavior of the nanocomposites was evaluated through differential scanning calorimetry (DSC), and it was observed that addition of GNPs into PET powders at 10% increased the crystallinity of the PET 50%. Confocal microscopy confirmed that mixing GNP with PET powders results in a more uniform distribution of the GNPs in the matrix compared to the mixture with PET pellets. X-ray diffraction (XRD) analysis confirmed the presence of GNPs with preferred orientation within the PET matrix.

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Graphical abstract GNP distribution analysis in melt-compounded PET nanocomposites

     

Impact of compression molding conditions on the thermal and mechanical properties of polyethylene

Compression molding is a current technique in polymer processing. Despite numerous studies, effect of molding pressure on physical properties has surprisingly not been fully investigated. In this study, the thermal and mechanical behavior of the compression‐molded polyethylene were thus explored to better grasp the relationship between processing parameters and ensuing properties. The effect of the molding temperature, pressure, cooling rate, and temperature profile on the tensile and flexural moduli as well as melting point of polyethylene was studied. We conclude that higher tensile and flexural moduli are obtained by increasing pressure and molding temperature, as well as decreasing the cooling rate. Our results were corroborated by X‐ray diffraction and differential scanning calorimetry measurements. Moreover, the use of a temperature gradient with different temperatures for the upper and bottom plates of the mold leads to asymmetric samples whose tensile and flexural moduli are improved. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46176.     

Effects of a hindered phenol compound on the dynamic mechanical properties of chlorinated polyethylene,acrylic rubber,and their blend

The dynamic mechanical properties of binary hybrids of chlorinated polyethylene (CPE) and acrylic rubber (ACM) with 3,9‐bis{1,1‐dimethyl‐2[β‐(3‐tert‐butyl‐4‐ hydroxy‐5‐methylphenyl)propionyloxy]ethyl}‐2,4,8,10‐tetraoxaspiro[5,5]‐undecane (AO‐80) and their ternary hybrids were investigated. The addition of AO‐80 was successful in tailoring the damping profile. The ACM/AO‐80 hybrids show only one relaxation, which is larger than that of pure ACM, whereas for the CPE/AO‐80 hybrids, one novel relaxation appears above the glass‐transition temperature of CPE. In the case of CPE/AO‐80/ACM, a supramolecular network was formed by a crosslink due to hydrogen bonding. The replacement of a part of CPE by ACM increased the value in the middle of two peaks. The AO‐80 molecule, which is a bifunctional hydrogen‐bonding acceptor, was found to act as a compatibilizer. In addition, in such ternary hybrids, the tan δ value in the middle of the two peaks was found to be proportional to the slope of the E′ curve at an identical temperature. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2468–2473, 2001     

Enhanced mechanical and thermal properties of nanodiamond reinforced low density polyethylene nanocomposites

In this study, the reinforcement effects of low-content hydrophilic nanodiamond (ND) on linear low-density polyethylene (PE) nanocomposites were investigated. ND was incorporated in PE via simple solution blending. The obtained PE/ND nanocomposites were characterized using scanning electron microscopy, ultraviolet–visible spectra, X-ray diffraction, tensile test, thermogravimetry, and differential scanning calorimetry. Generally, PE/ND nanocomposites with poor interfacial interaction cause large agglomerates, resulting in brittle and poor mechanical properties. Owing to the different natures of non-polar PE and polar ND, the higher the ND content, the larger the agglomerates formed in the nanocomposites. However, PE/ND nanocomposites show unique mechanical properties, that is, the Young's modulus, tensile strength, elongation at break, and toughness increased upon the incorporation of ND. The Young's modulus of the PE/ND nanocomposites exceeded the theoretical value calculated using the Halpin–Tsai model. In addition, the toughness increased by 18% at only 0.5 wt% ND loading. Furthermore, there was an increase in the thermal degradation temperature, melting temperature, and crystallization temperature.     

Nanocomposites of poly(vinyl chloride) and nanometric calcium carbonate particles: Effects of chlorinated polyethylene on mechanical properties,morphology, and rheology

Nanocomposites of poly(vinyl chloride) (PVC) and nano‐calcium carbonate (CaCO₃) particles were prepared via melt blending, and chlorinated polyethylene (CPE) as an interfacial modifier was also introduced into the nanocomposites through preparing CPE/nano‐CaCO₃ master batch. The mechanical properties, morphology, and rheology were studied. A moderate toughening effect was observed for PVC/nano‐CaCO₃ binary nanocomposites. The elongation at break and Young's modulus also increased with increasing the nano‐CaCO₃ concentration. Transmission electron microscopy (TEM) study demonstrated that the nano‐CaCO₃ particles were dispersed in a PVC matrix uniformly, and a few nanoparticles agglomeration was found. The toughening effect of the nano‐CaCO₃ particles on PVC could be attributed to the cavitation of the matrix, which consumed tremendous fracture energy. The notched Izod impact strength achieved a significant improvement by incorporating CPE into the nanocomposites, and obtained the high value of 745 J/m. Morphology investigation indicated that the nano‐CaCO₃ particles in the PVC matrix was encapsulated with a CPE layer through preparing the CPE/nano‐CaCO₃ master batch. The evaluation of rheological properties revealed that the introduction of nano‐CaCO₃ particles into PVC resulted in a remarkable increase in the melt viscosity. However, the viscosity decreased with addition of CPE, especially at high shear rates; thus, the processability of the ternary nanocomposites was improved. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2714–2723, 2004     

Studies on thermal,mechanical, morphological,and viscoelastic properties of polybenzimidazole fiber reinforced high density polyethylene composites

High density polyethylene (HDPE) and polybenzimidazole fiber (PBI) composites were prepared by melt blending in a twin screw extruder. The thermomechanical properties of PBI fiber reinforced HDPE composite samples (1%, 4%, and 8%) of fiber lengths 3 mm and 6 mm were investigated using differential scanning calorimeter (DSC), universal testing machine, rheometer, and scanning electron microscopy (SEM). The effects of fiber content and fiber lengths on the thermomechanical properties of the HDPE‐PBI composites were studied. The DSC analysis showed a decrease in crystallinity of HDPE‐PBI composites with an increase of fiber loading. SEM images revealed homogeneous distribution of the fibers in the polymer matrix. The thermal behavior of the composites was evaluated from thermogravimetric analysis and the thermal stability was found to increase with the addition of fibers. The evidence of homogeneous distribution was verified by the considerably high values of tensile strength and flexural strength. In the rheology study, the complex viscosities of HDPE‐PBI composites were higher than the HDPE matrix and increased with the increasing of PBI fiber loading. POLYM. COMPOS., 5–13, 2016. © 2014 Society of Plastics Engineers     

Relation between the microstructure and the dynamical mechanical properties of rigid PVC modified by chlorinated polyethylene

Dynamic mechanical properties of biphasic PVC/CPE polymer blends of different micromorphology were studied. It was revealed that a considerable interaction existed between the polymers involved in the high-impact polymer blends. It was established that the most favorable cold impact strength of the high-impact PVC/CPE alloy was obtained when a structure of mixed morphology had been formed in the course of processing. As indicated by the DMA spectra, more marked plasticizing effect of CPE appeared at a lower thickness of CPE layer among the primary globules, i.e., at a higher extent of wetting the PVC globules by CPE molecules. This phenomenon is manifested by splitting the β-relaxation transition of PVC.     

Low density polyethylene composites reinforced with Australian King Palm fibers: mechanical and thermal properties

The aim of this work is to obtain and evaluate the mechanical and thermal properties of low Density Polyethylene (LDPE) composites reinforced with fibers from Australian King Palm fibers. Raw fibers were characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) Spectroscopy. The chemical composition of the fibers was also evaluated. After characterizing the fibers were mixed into the LDPE, in proportions of 5, 10, 15 and 20% (wt/wt) using a thermokinetic mixer model MH-50H. Furthermore tensile, flexural and impact specimens were prepared for evaluation of mechanical properties. The composites were analyzed through SEM micrographs of fractured surfaces and thermal analysis. The results indicate that the reinforcement decreases the thermal stability of the composites, but caused an increase the mechanical properties of the composites. The composites reinforced with of raw fibers 20% (wt/wt) showed significant increase in the tensile strength, flexural and impact.     

High density polyethylene/ultra high molecular weight polyethylene blend. II. Effect of hydroxyapatite on processing,thermal, and mechanical properties

Hydroxyapatite (HA) is part of bone mineral composition. Several attempts have been made to incorporate HA into high density polyethylene (HDPE) to produce bone replacement biomaterials since neat HDPE is not suitable as bone replacement. The blending of HDPE with ultra high molecular weight polyethylene (UHMWPE) up to 50% by weight was performed with the aim of improving the toughness of composites. Reinforcement of blend with HA of up to 50% by weight was carried out. Methods of characterizing the composites included density, differential scanning calorimetry, thermal gravimetric analysis, ash content, and morphological examination using scanning electron microscope. For the mechanical properties of the composites, tensile, flexural, and impact tests were carried out. Incorporation of HA into HDPE has resulted in the brittleness of the composites. Blending of HDPE with UHMWPE in the presence of HA was found to improve the mechanical properties and promote a ductile failure of the resulting composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3931–3942, 2006     

氯化顺丁橡胶动态力学性能的研究

应用RPA2000型橡胶加工分析仪研究氯化顺丁橡胶（CBR）的动态力学性能，并与BR和CR进行对比。试验结果表明，在试验温度范围内，CBR硫化胶的储能剪切模量（G′）大=FBR，损耗因子（tanδ）小于BR和CR；在试验频率范围内，CBR硫化胶的G′大于BR和CR，tanδ小于CR和BR（高频下）；在试验应变范围内，CBR硫化胶的G′大于BR和CR，tanδ与BR相差不大但小于CR。     

氯化聚乙烯接枝水溶性单体共聚物的双亲性

以疏水性弹性体氯化聚乙烯(CPE)接枝水溶性单体(丙烯酸AA,丙烯酰胺AM)合成双亲性接枝聚合物(CPE-g-AA,CPE-g-AM)。考察了接枝物的吸水率及亲水/亲油性能。研究发现,双亲性接枝聚合物吸水性能与接枝单体类型及其接枝率有关,接枝物在油/水混合液中的分散状况及吸水/油性能与接枝物的接枝率及所吸有机溶剂溶度参数(δ)有关,随极性单体接枝链含量增大,双亲性接枝物吸水性增强而吸油性降低。