Fabrication of Super Tough Polycarbonate/Styrene-Etylene-Butylene-Styrene Grafted Maleic Anhydride (SEBS-g-MA) Blends: Morphological,Short Term Static Mechanical and Fracture Performance Interpretation

Impact behaviours, tensile properties and fracture performance of polycarbonate (PC)/styrene ethylene-butylene-styrene-grafted-maleic anhydride (SEBS-g-MA) copolymer blends at SEBS-g-MA volume fraction Φ_d = 0–0.39 are evaluated. In presence of rubber a significant augmentation in notched Izod impact strength was observed while tensile modulus and strength decreased. Morphological studies reveal good interaction between the PC and the rubber particles showing homogeneous dispersion of SEBS-g-MA in the polycarbonate matrix. Interparticle distance of the dispersed phase evaluated from the morphology studies by scanning electron microscopy (SEM) and the impact strength dependence on the concentration of the blending rubber were analysed. The essential work of fracture approach is applied to study fracture properties of the blends. With increasing SEBS-g-MA concentration nonessential or plastic work increased which explained the enhancement of impact strength of blends.     

Mechanical Properties of Impact i-PP/CSM Rubber Blends

ABSTRACT

The impact strength and the tensile behavior of an impact grade of isotactic polypropylene (impact i-pp)/chlorosulfonated polyethylene (CSM) rubber blends are studied at the CSM rubber concentrations 0 to 23.4 vol%. The impact strength, which increased with CSM rubber concentration, has been analyzed on the basis of the interphase adhesion and crazing mechanisms. Tensile modulus and strength decreased whereas breaking elongation increased with increase in CSM rubber content. Predictive models have been used to explain the tensile modulus and strength properties. Scanning electron microscopy has been employed to study the phase structure.     

Effect of Rubber Content of ABS on Properties of PC/ABS Blends. I. Rheological,Mechanical, and Thermal Properties

ABSTRACT

The effect of rubber content of poly (acrylonitrile butadiene styrene) (ABS) on compatibility and properties of polycarbonate (PC)/ABS blend systems has been investigated. The rheological, mechanical, physical, and thermal properties of PC/ABS blend systems containing ABS of different rubber content were studied. The reduced torque data on Torque Rheocord indicated improved processability of PC by addition of ABS, however, in ABS-rich compositions, higher rubber content reduces the extent of improvement. The tensile strength of PC decreased with addition of ABS to it but PC-rich compositions have a nearly additive response. The deviation form additivity for blends having higher rubber ABS was more pronounced. However, the impact strength of blends having higher rubber ABS were higher than other types and showed a positive deviation from additivity with variation in compositions. The blends containing ABS with lower rubber content showed a single glass-transition temperature (Tg) in differential scanning calorimetry studies (DSC) in the whole composition range indicating miscibility. Although two Tgs, one associated with PC phase and one with ABS phase, were observed for blends containing high rubber ABS, the shift in Tgs with respect to pure component values indicates partial miscibility. The decrease in the extent of shift with increase of ABS in these blends indicates undesirable phase separation due to poor adhesion of higher level of rubber content.     

Compatibility,adhesional interaction of components,impact strength,and rheological behavior of polycarbonate/polycarbonate‐siloxane block copolymer

Polycarbonate (PC) blended with a polymer‐modifier polycarbonate–polydimethylsiloxane (PC–PDMS) of polyblock structure having equal molar ratios of soft (PDMS) and hard (PC) blocks have been investigated. The kinetics of adhesional interaction in blends and the analysis of interphase interaction conducted by using the relaxation spectrometry showed that intensive interactions between phases can occur. At a concentration of the modifier ≤5 wt %, these effects can lead to a partial compatibility of the components. The phase separation comes to completion when PC–PDMS content reaches 7 to 10 wt %. Here the impact strength of the blends improves compared with homopolycarbonate; this factor becomes less sensitive to the notch pattern or surface defects. The micro‐heterogeneous blends would fail by the multiple crazing mechanism. The mode of temperature vs impact strength relationship depends on the concentration of the modifier. Low shearing rates applied to the PC blends containing 3 to 7 wt % of PC–PDMS results in a lower melt flow index compared with that for a neat PC. The blends were more sensitive to shearing stresses than the homopolycarbonate. Therefore, they have lower viscosity at a high shearing rate than PC. Introduction of PC–PDMS into PC did not change its thermal stability significantly. The modifier inhibited the chemical crosslinking of PC chains if the melt had been kept for a long period. The optimal mechanical properties combined with improved processability were found in blends containing 7 to 10 wt % of PC–PDMS. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 858–869, 2000     

ABS树脂中胶含量对PC/ABS合金性能及微观结构的影响

采用胶含量(质量分数,下同)为60％的丙烯腈-丁二烯-苯乙烯接枝共聚物(ABS)接枝粉料与苯乙烯-丙烯腈共聚物(SAN)以不同比例进行共混,制备了胶含量范围为10％～55％的ABS树脂.将胶含量不同的ABS树脂与聚碳酸酯(PC)以30/70、50/50、70/30的质量比利用熔融共混技术,制备了组成不同的PC/ABS共混物,考察了ABS树脂胶含量对不同组成的PC/ABS合金性能的影响.研究结果表明:随着ABS树脂中胶含量的增加,ABS树脂的冲击强度不断提高,屈服强度、模量及熔体流动速率逐渐降低.随着PC/ABS合金中ABS胶含量的增加,合金的冲击强度显著提高,ABS树脂中胶含量大于30％以后,合金的冲击强度变化不大,且3种组成的PC/ABS合金的冲击强度相差不大.合金的屈服强度、模量及熔体流动速率却随着ABS中胶含量的增加不断降低,其中组成为30/70的PC/ABS合金最低.利用扫描电镜观察了PC/ABS组成为70/30合金的微观结构,研究表明,ABS树脂形成连续相,PC为分散相,随ABS树脂胶含量的增加,合金的相形态变得更精细.     

Studies on polycarbonate-viton GF blends

The effect of addition of different amounts of Viton GF, a fluoroelastomer, on the properties of polycarbonate (PC) was investigated. A significant improvement in impact strength (ca. 100%) was observed on addition of 20 wt.-% of Viton GF. Thermal and dynamic mechanical behaviour of the blends was also investigated. The morphology of these blends was studied by scanning electron microscopy which revealed an uniform distribution of rubber cavities in polycarbonate matrix. The number of rubber cavities increased with increase of rubber content. Erosive wear studies were carried out on compression moulded sheets of PC and PC/Viton GF blends using a sand blasting rig. The effect of impact angle and the amount of abrasive used on the erosive behaviour was investigated. Polycarbonate showed a maximum erosion at an impact angle of 30°. A reduction in specific erosion was observed with increasing concentration of elastomer in the blends.     

Mechanical Properties and Morphology of Nitrile Rubber Toughened Polystyrene

Mechanical properties and morphology of blends of polystyrene and finely powdered (uncrosslinked and crosslinked) nitrile rubber were studied with special reference to the effect of blend ratio. Blends were prepared by melt mixing polystyrene and nitrile rubber in an internal mixer at 180°C in the composition range of 0–20 wt% nitrile rubber. The tensile stress/strain properties and impact strength of the polystyrene/nitrile rubber blends were determined using injection molded test specimens. In comparison to the blends with uncrosslinked nitrile rubber, blends with crosslinked nitrile rubber showed higher tensile strength, elongation at break, Young's modulus, impact strength, flexural strength, and flexural modulus. The enhanced adhesion between the dispersed nitrile rubber phase and the polystyrene matrix results in an increase in mechanical properties. Scanning electron micrographs of the fractured surfaces confirm the enhancement in mechanical properties.     

PA6/ABS共混物性能研究

将聚酰胺6（PA6）与市售的丙烯腈-丁二烯-苯乙烯（ABS）树脂共混,制备PA6/ABS共混物。研究了ABS树脂的用量对PA6/ABS共混物力学性能的影响;采用苯乙烯及丙烯腈共聚物（SAN）和ABS粉料熔融共混制得不同胶含量的ABS/SAN共混物。研究了不同胶含量的ABS/SAN共混物对PA6/ABS共混物力学性能的影响。在PA6/ABS/SAN共混物中引入苯乙烯-丙烯腈-马来酸酐共聚（SAM）树脂取代部分SAN树脂,研究了SAM树脂的加入及引入顺序的不同对共混物性能的影响。结果表明, ABS树脂的用量在50%～60%左右时共混物性能最佳。随ABS/SAN共混物胶含量提高,共混物的拉伸强度、弹性模量、弯曲强度和弯曲模量逐渐降低。随SAM树脂替代SAN量增加,共混物的拉伸和弯曲性能先降低后增加。但共混物熔体流动速率降低明显,而SAM树脂的引入顺序对共混物的力学性能影响不大。     

废胶粉/聚丙烯接枝物共混材料的制备与性能

采用熔融接枝法分别制备了高强度和高熔体流动速率的聚丙烯接枝马来酸酐共聚物,以改善聚丙烯与胶粉间的界面相容性,提高废胶粉/聚丙烯接枝物共混材料的力学性能和流动性.力学性能测试结果表明,随着废胶粉用量的增加,废胶粉/聚丙烯接枝物共混材料的拉伸性能下降,扯断伸长率和缺口冲击强度均增大,熔体流动速率减小,流动性变差.由热重分析...     

Effect of octene content in poly(ethylene‐co‐1‐octene) on the properties of poly(propylene)/poly(ethylene‐co‐1‐octene) blends

Ethylene‐octene random copolymer (EOC) is one of the most commonly employed elastomers for PP, and as such its rubber toughening efficiency has been extensively studied. However, most existing studies employ EOC containing an octene comonomer of about 8 mol %. Therefore, in this study, we investigated the effect of EOC octene comonomer content on the morphology and thermal and mechanical properties of PP‐ethylene random copolymer (PP‐CP)/EOC (80/20 wt %/wt %) blends. It was clearly shown that the properties of the blends are significantly affected by the octene content. The rubber particle size of the blends decreased as the octene content in the EOC was increased, which was a consequence of the reduced interfacial tension between PP‐CP and EOC. Impact strength of the blends as a function of octene content displayed a brittle‐ductile transition. The tensile yield strength and modulus of the PP‐CP/EOC blends were decreased by addition of EOC, owing to incorporation of the soft EOC into the hard PP‐CP. The tensile yield strength and modulus of PP‐CP/EOC blends decreased monotonically with the octene content in the EOC. The melting temperature as well as the crystallinity of the PP‐CP phase were not affected significantly by the addition of EOC whereas a notable shift in melting and crystallization temperatures was observed for the EOC phase. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1133–1139, 2007     

Mechanical and thermal behavior of poly(acrylonitrile-butadiene-styrene)/polycarbonate blends reinforced with potassium titanate whiskers

Poly(acrylonitrile-butadiene-styrene) (ABS)/polycarbonate (PC) blends reinforced with potassium titanate (K₂Ti₆O₁₃) whiskers were prepared in a twin screw extruder followed by injection molding. The whiskers were pretreated with tetrabutyl orthotitanate prior to compounding. The tensile, dynamic mechanical, impact, morphology and thermal properties of the blends were studied. Tensile tests showed that the modulus of ABS/PC/K₂Ti₆O₁₃ blend increased markedly with increasing whisker content. However, the variation of the modulus of ABS/PC/K₂Ti₆O₁₃ blend with PC content followed a sigmoidal relation. In addition, the tensile strength of the blends containing 20 wt% PC tended to increase markedly with increasing whisker content. But the impact strength of the blends containing 20 wt% PC decreased rapidly with increasing whisker content. Dynamic mechanical analyses (DMA) results indicated that the storage modulus of the blends increased markedly with increasing K₂Ti₆O₁₃ whisker content. Differential thermal analysis and thermogravimetric measurements showed that potassium titanate whiskers tend to induce chemical decomposition of PC during blending of the PC/whisker blends. However, the incorporation of ABS into PC was beneficial to reduce the PC decomposition during compounding with the whiskers.     

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., 57:1016–1027, 2017. © 2016 Society of Plastics Engineers     

The Influence of NBR-g-GMA Compatibilizer on the Morphology and Mechanical Properties of Poly (ethylene terephthalate)/Polycarbonate/NBR Ternary Blends

The work aims to study the role of NBR-g-GMA compatibilizer on the morphology and mechanical characteristics of PET/PC/NBR ternary blends. The compatibilizer content and amount of constitutive polymers are changed to correlate morphology development with mechanical properties. Various ternary samples are prepared using a twin-screw extruder whereat weight percent of rubbery dispersed phase (NBR+NBR-g-GMA) is changed. Analyzing the morphology of produced samples and interpretation of mechanical properties corroborated the role of the mentioned factors on the type of morphology and also the size of both individual and composite domains in these sorts of ternary blends. Based on this attempt, the mechanical properties of 50/50 blends of NBR/NBR-g-GMA, showed maximum toughness value compared to pure PET specimen. Also, the results revealed that by increasing the rubber content, the rodlike structures were disappeared; besides, toughness was increased. On the contrary, by increasing PC content, rodlike structures have seen by morphological study; however, core-shell droplets formed in the blend structure caused enhancing the impact strength and reducing Young's modulus. Ultimately, the ternary blend of 63/7/30 of PET/PC/ (NBR+NBR-g-GMA) revealed the best mechanical properties due to proper interaction between the PET matrix and rubbery domains in the presence of reactive compatibilizer.     

氯化丁基橡胶/聚丙烯酸酯阻尼橡胶的力学性能

采用聚丙烯酸酯(PA)为第二组分,与氯化丁基橡胶（CIIR)制备了CIIR／PA阻尼橡胶,分析了CIIR／PA共混物的结构,讨论了原料组成、交联剂用量和填料种类对其力学性能的影响、结果表明,CIIR／聚(丙烯酸乙酯-甲基丙烯酸丁酯)[P(EA-BMA)]共混物的正硫化时间为10min．CIIR／聚丙烯酸乙酯(PEA)硫化共混物中存在共交联结构;共交联CIIR／PEA共混物形成了双相连续的微观相态结构;当P(EA-BMA)中PBMA链段的质量分数增加到20%时,共交联CIIR／P(EA-BMA)共混物的拉伸强度和100％定伸应力下降,当P(EA-BMA)中PBMA链段的质量分数继续增加,共混物的拉伸强度和100％定伸应力又逐渐上升,当酚醛树脂(PR)用量不大于20份时,随着PR用量的增加,共交联CIIR／PEA共混物的100％定伸应力和邵尔A型硬度增大,拉伸强度和扯断伸长率减小;当PR用量为30份时,共混物的100％定伸应力减小,拉伸强度增大;填料中以炭黑的增强效果最好,玻璃微球增强效果最差。     

Blends of polyacetal and ethylene-octene elastomer: Mechanical,dynamic mechanical and morphological properties

Polyacetal (POM) and ethylene octene copolymer(EOC) elastomers form immiscible blends with extremely low compatibility. In order to improve the dispersion, stability and properties of these blends, dynamic vulcanization was carried out in a twin screw extruder using dicumyl peroxide. The tensile strength decreased with increase in % elongation at break for both blend systems. There was a drastic decrease in impact strength for unvulcanized blends as the elastomer content increased and this was attributed to the coalescence of the elastomer particles as their content increased. In the case of dynamically vulcanized blends there was a significant increase in impact strength as the levels of elastomer increased. Dynamic mechanical analysis has been carried out to investigate the effect of blend composition and dynamic vulcanization on dynamic mechanical parameters such as storage modulus, loss modulus and loss factor. The results indicate gross incompatibility of POM and EOC blends. However, dynamically vulcanized blends show better adhesion between component polymers. The morphological studies reveal that the particle size and coalescence of elastomer was significantly reduced in comparison to unvulcanized bends. The phase adhesion was improved by dynamic vulcanization. Hence, it was observed that dynamic vulcanization effectively improves the morphology of the blend system and enhances the properties of polyacetal.     

The Effect of Dynamic Vulcanization on the Properties of Polypropylene/Ethylene-Propylene Diene Terpolymer/Natural Rubber (PP/EPDM/NR) Ternary Blend

The effects of dynamic vulcanization on the process development and some properties, such as tensile properties, swelling index, gel content, crystallinity, and morphology, of the polypropylene (PP)/ethylene-propylene diene terpolymer (EPDM)/natural rubber (NR) blends were investigated. Dynamically vulcanized blends show higher stabilization torque than unvulcanized blends. In terms of tensile properties, the tensile strength and tensile modulus (stress at 100% elongation, M₁₀₀) of the vulcanized blends have been found to increase as compared with the unvulcanized blends, whereas the elongation at break is higher in the blend with richer EPDM content. These results can be attributed to the formation of cross-linking in the rubber phase. The formation of cross-links in the rubber phase has also been proved by swelling index and gel content. The percentage of crystallinity of the blends is decreased by dynamic vulcanization. Scanning electron microscopy (SEM) micrographs from the surface extraction of the blends support that the cross-links occurred during dynamic vulcanization.     

Mechanical and Morphological Properties of PP/LLPDE/NR Blends—Effects of Polyoctenamer

In this study, impact-modified polypropylene (PP) ternary blends based on PP/natural rubber (NR)/linear low-density polyethylene (LLDPE) with ratios of 72/10/18 and 64/20/16 were produced by a twin-screw extruder with polyoctenamer (TOR) as the compatibilizer. The mechanical properties of the blends were determined on injection-molded specimens in tensile, flexural, and impact testing. The impact strength and elongation at break of the blend increased significantly while the flexural modulus and tensile strength decreased slightly with increasing TOR content. The impact strength improved with the increasing TOR due the increase of interfacial adhesion resulting in finer dispersion of the rubbery minor phase in the PP matrix. The improvement in compatibility with the addition of TOR into PP/NR/LLDPE blends is being supported by both scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA).     

Deformation of rubber-toughened polycarbonate: Macroscale analysis of the damage zone

Two commercial core-shell rubbers were used as impact modifiers for polycarbonate (PC). Specimens with a single semicircular edge notch were stretched uniaxially in order to study the prefracture damage evolution of blends under a triaxial tensile stress state. The irreversible deformation of modified PC included a cavitation mechanism in addition to the three shear modes of unmodified PC. At the macroscopic level, the cavitation condition could be described by a mean stress concept. The corresponding critical volume strain for cavitation in PC blends was determined to be independent of rubber content but differed for the two impact modifiers. The critical volume strain for cavitation was used as an index of cavitation resistance for the impact modifiers. The effect of rubber content and temperature on Izod impact strength of the PC blends was also reported. From the relationship between the cavitation resistance and the Izod impact strength, it was proposed that impact modifiers with a higher cavitation resistance impart better toughness to blends with PC. © 1994 John Wiley & Sons, Inc.     

马来酸酐接枝三元乙丙橡胶共聚物增容AES/PC共混物的研究

研究了马来酸酐接枝三元乙丙橡胶共聚物（EPDM-g-MAH）作为增容剂对丙烯腈三元乙丙橡胶苯乙烯共聚物/聚碳酸酯（AES/PC）（70/30）共混物结构和性能的影响。结果表明,EPDM-g-MAH作为反应型增容剂,能有效地减小低橡胶含量的AES/PC共混物中PC分散相的粒径,提高共混物的力学性能;当EPDM-g-MAH用量为3份时,橡胶含量为21 %的AES/PC共混物的缺口冲击强度提高近1倍,同时能保持较高的拉伸强度和热变形温度。     

Mechanical Properties of Talc Filled i-PP/CSM Rubber Composites

ABSTRACT

Tensile and impact properties of talc-filled i-PP/CSM rubber (20 phr, 0.13 vol fraction) blends were studied in the talc concentration range 0–0.149 vol fraction (0–50 phr). The tensile modulus increased whereas the tensile breaking strength and the strain-at-break decreased with increase in the talc concentration. The modulus increase and the strain decrease were due to enhanced mechanical restraint imposed by the talc particles on the polymer blend decreasing its deformability. Formation of stress concentration points explained the decrease in the tensile strength. The Izod impact strength showed a significant decrease with increase in the filler content. Surface treatment of the talc particles with a titanate coupling agent LICA 12 increased the wetting of the talc by the polymer blend, further modifying the strength properties. Scanning electron microscopic studies showed enhanced dispersion of the filler particles sequential to the surface treatment, effecting modifications of the composite strength properties.