Morphology Formation in PC/ABS Blends during Thermal Processing and the Effect of the Viscosity Ratio of Blend Partners (original) (raw)
Related papers
Some Mechanical and Thermal Properties of PC/ABS Blends
Materials Sciences and Applications, 2011
A series of blends of Acrylonitrile-Butadiene-Styrene (ABS) and Polycarbonate (PC) were prepared and some of their thermal and mechanical properties were determined. The Young's modulus changed gradually and monotonically with the polycarbonate content. This effect was tentatively explained as the antiplasticization of the PC which is ascribed to the chain mobility, which permits the PC chains to pack more tightly, to the secondary cross-linking between the PC chains, or to the secondary attachment of bulky side-chains to the PC, thus producing steric hindrance to the rotation of the PC main chains. The experimental values found for the impact strength were intermediate between those of the neat polymers, depending upon the dispersed rubber particles of butadiene in the matrix of SAN (Styrene-Acrylonitrile), and the dispersed PC particles which generally make the ABS more brittle. A maximum value of about 88 KJ/m 2 for the impact strength was observed for the blend with 90% PC. This may be attributed to the strong polymer-polymer interactions for this particular composition. The variations in the heat deflection temperature HDT and the Vicat softening point with the blend composition were very similar, and allowed us to assume that the phase inversion between the matrices of the two polymers takes place at 50% PC. The morphology of the blends revealed by SEM observation, show a co-continuous structure.
1997
A styrene-acrylonitril copolymer (SAN) was toughened by SAN-grafted polybutadiene core-shell rubber particles. Notched tensile specimens were fractured with a tensile speed ranging from 10 !4 to 10 m s !1. The deformation processes close to the fracture surface were studied by means of transmission electron microscopy. A marked difference in the structure of the deformation zone was observed between low speed (10 !3 m s !1) and high speed (51 m s !1) deformed samples. At low tensile speed the structure of the deformation zone correlated closely with fracture mechanics theory. When the tensile speed was increased the deformation zone had a layered structure. In the zone 400-1.5 m below the fracture surface the deformation structure was similar to that at low speed. In the layer 1.5-0.5 m from the fracture surface the rubber particles were strongly deformed, but no cavities or crazes could be observed. Directly next to the fracture surface the high speed deformation zone showed a small layer (0.5 m) where all the deformation had vanished. It is suggested that due to high strain-rate plasticity at the crack tip a temperature rise occurs which is high enough to cause complete relaxation of the deformation in this layer. Therefore, locally the glass transition temperature of the matrix material was reached. The interaction between thermal effects and deformation processes at the crack tip is discussed.
Polystyrene+ Styrene-Butadiene Blends: Mechanical and Morphological Properties
2004
Blends of 3, 5 and 10 weight % of styrene-butadiene rubber (SBR) embedded in a rigid polystyrene matrix were first mixed in a co-rotating twin screw extruder and then injection molded. The blends were characterized in terms of: tensile strength, flexural strength and Izod impact and morphology by scanning electron microscopy (SEM). The addition of SBRs improves impact strength but lowers tensile and flexural modulae. Homogeneous distribution of the reinforcing phase enhances the impact strength. Best results are obtained for linear SBRs.
Materials Science and Engineering
This work follows up that reported in a previous paper in which the impact fracture behaviour of polyvinylchloride (PVC)-(acrylonitrile-butadiene-styrene (ABS) terpolymers) blends was examined in relation to composition. The study of property-composition and property-structure relationships in these materials is extended here to other properties of both technological and fundamental interest, namely density, elastic modulus, glass transition temperatures and heat deflection temperature. In this investigation, PVC-ABS blends are regarded as a three.polymer system PVC-butadiene rubber (BR)-(styrene-acrylonitrile (SAN) copolymer), the blend composition to be investigated was systematically varied accordingly. From the property-composition data obtained, structural indications of fundamental interest are also drawn: PVC and SAN appear to make distinct glassy phases both in the absence and in the presence of .SAN-grafted BR particles.
ANNALS OF THE ORADEA UNIVERSITY. Fascicle of Management and Technological Engineering., 2013
A binary blend Acrylonitrile Butadiene Styrene-High Impact Polystyrene (ABS-HIPS 50% wt) was prepared on a twin-screw extruder at 190-210 ºC. The different mechanical properties were then analyzed using tensile strength and impact tests. The analysis of mechanical properties showed a decrease in elongation at break and impact strength. On the other hand, we have prepared ternary blends of ABS-HIPS-Styrene Ethylene Butylene Styrene (SEBS), varying the percentage of SEBS from 10 to 30 %wt using a twin screw extruder at 190-210ºC. The addition of SEBS to the binary system (ABS-HIPS) allowed us to increase the ductile properties (elongation at break and impact strength).
Journal of Applied Polymer Science, 2009
PS/AES blends were prepared by in situ polymerization of styrene in the presence of AES elastomer, a grafting copolymer of poly(styrene-co-acrylonitrile) -SAN and poly(ethylene-co-propylene-co-diene)-EPDM chains. These blends are immiscible and present complex phase behavior. Selective extraction of the blends' components showed that some fraction of the material is crosslinked and a grafting of PS onto AES is possible. The morphology of the noninjected blends consists of spherical PS domains covered by a thin layer of AES. After injection molding, the blends show morphology of disperse elastomeric phase morphology in a rigid matrix. Two factors could contribute to the change of morphology: (1) the stationary polymerization conditions did not allow the mixture to reach the equilibrium morphology; (2) the grafting degree between PS and AES was not high enough to ensure the morphological stability against changes during processing in the melting state. The drastic change of EPDM morphology from continuous to disperse phase has as consequence a decrease in the intensity of the loss modulus peaks corresponding to the EPDM glass transition. However, the storage modulus at temperatures between the glass transition of EPDM and PS/SAN phases does not change significantly. This effect was attributed to the presence of the SAN rigid chains in the AES.
MECHANICAL PROPERTIES OF HIGH IMPACT ABS/PC BLENDS - EFFECT OF BLEND RATIO
Polymer blends are capable of providing materials which extend the useful properties beyond the range that can be obtained from single polymer equivalents. Blends of Acrylonitrile-Butadiene-Styrene (ABS) and Polycarbonate (PC) were prepared in different ratios by melt blending technique which was carried out using a twin screw extruder. A super high impact ABS at different weight ratios was incorporated into the blends to study the effects of blend ratio on the properties of the blend. This study focused upon tensile, flexural, impact and creep properties of ABS/PC blends. PC offered an improvement in tensile properties for this blend. With the increasing content of PC in ABS/PC blends, both the tensile strength and Young's Modulus of the blends were increased. Both the flexural strength and modulus show a marked increase with increasing PC content. In general, impact strength increases with increasing PC content. However, sudden drop in the impact strength value occurred when small amount of PC (20 wt%) was added to the blends. The creep resistance of neat PC exhibited the highest value while neat ABS has the lowest value. The optimum formulation for the ABS/PC blends based on the mechanical properties and cost is 40: 60 ABS/PC blend ratio.
Journal of Applied Polymer Science, 2017
In the challenging prospect of developing new materials by mixing different polymers to reach a synergetic performance, the present research focuses on the study of the miscibility of two polymers: The acrylonitrile butadiene styrene (ABS) composed of a dispersed elastomeric (polybutadiene rubber) polymer embedded in a SAN thermoplastic matrix, and the polycarbonate (PC). It shall be noted that obtaining miscible polymer blends is often a difficult task because of the large size of their molecular chains and the high interfacial tension between the polymer phases. Until now, the most numerous researches developed in this field involve polymer blends obtained by compatibilization techniques in order to improve the interfacial adhesion between initial polymers. The aim of this work is to study the miscibility between ABS and PC. First, two different methods were used to mix the polymers: the twinscrew extrusion and the dissolution in a common solvent tetrahydrofuran (THF). Then, physicochemical, microscopic observation and rheological characterization were performed on samples of mixtures obtained by both extrusion processing and dissolution method. The measurement of glassy transition temperature (T g) by differential scanning calorimetry measurements (DSC) and dynamical mechanical thermal analysis (DMTA) have shown a partial miscibility between the two polymers