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Compatibilized Blends (compatibilized + blend)

Distribution by Scientific Domains

Polymers and Materials Science	85%

Selected Abstracts

Morphology of poly(ethylene terephthalate) blends: An analysis under real processing conditions by rheology and microscopy

ADVANCES IN POLYMER TECHNOLOGY, Issue 3 2009
lhan Özen
Abstract The present work describes the formation of co-continuous phase morphologies in uncompatibilized and compatibilized poly(ethylene terephthalate) (PET),poly(m -xylene adipamide) (MXD6) and PET, poly(ethylene- co -vinyl alcohol) (EVOH) melt-extruded blends. Phase continuity has been determined by using the Jordhamo relationship. Viscosity values, which are essential for the calculation of the phase continuity, have been obtained by capillary rheometry. Thermal behavior of the blends has been analyzed by employing differential scanning calorimetry and phase continuity has been investigated for the noncompatibilized and the compatibilized blends by scanning electron microscopy. PET,MXD6 blends [92.35:7.65 (v/v) and 84.5:15.5 (v/v)] and PET,EVOH blends [73.63:26.37 (v/v)] exhibit droplet-in-matrix phase morphology, whereas uncompatibilized PET,MXD6 [75.8:24.2 (v/v)] blend has a combination of rod-like, droplet,matrix structure, and quasi-interpenetrating network structure. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:173,184, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20156 [source]

Morphological, mechanical, and rheological studies of PVC/ABS blends in the presence of maleic anhydride

JOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 2 2010
Pegah Mohammad Hosseinpour
A novel method of enhancing compatibility in PVC/ABS blends is the use of ABS-grafted-(maleic anhydride) (ABS- g -MAH) as a compatibilizer. In this study, maleic anhydride was grafted onto ABS (initiated by peroxide) in an internal mixer. Grafting degree was determined by a back-titration method, and certain amounts of the resultant ABS- g -MAH were added to PVC/ABS blends during their melt blending in the mixer. The weight ratio of PVC to ABS was kept at 70:30. Evaluation of compatibilization was accomplished via tensile and notched Izod impact tests, scanning electron microscopy (SEM), and rheological studies. According to the SEM micrographs, better dispersion of the rubber phase and its finer size in properly compatibilized blends were indications of better compatibility. Besides, in the presence of a proper amount [5 parts per hundred parts of PVC (php)] of ABS- g -MAH, PVC/ABS blends showed significantly higher impact strengths than uncompatibilized blends. This result, in turn, would be an indication of better compatibility. In the presence of 5 php of compatibilizer, the higher complex viscosity and storage modulus, as well as a lower loss modulus and loss factor in the range of frequency studied, indicated stronger interfacial adhesion as a result of interaction between maleic anhydride and the PVC-SAN matrix. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers [source]

Functionalization of LDPE by Melt Grafting with Glycidyl Methacrylate and Reactive Blending with Polyamide-6

MACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 8 2003
Qian Wei
Abstract Low-density polyethylene (LDPE) was functionalized by melt radical grafting with glycidyl methacrylate (GMA) and employed for reactive blending with polyamide-6 (PA6). The effect of the reaction procedure on the grafting degree of LDPE- g -GMA samples (0.5,12.5 wt.-% GMA) was analyzed as a function of the concentration of GMA monomer, radical initiator (BTP), and addition of styrene as co-monomer. Optimized grafting conditions were obtained when the amount of the monomer is below 10 wt.-% and that of peroxide in the range 0.2,0.4 wt.-%. Binary blends of PA6 with LDPE- g -GMA (3.5 wt.-% GMA) and with LDPE at various compositions (80/20, 67/33, 50/50 wt.-%) were prepared in an internal mixer and their properties were evaluated by torque, SEM and DSC analyses. Morphological examination by SEM showed a large improvement of phase dispersion and interfacial adhesion in PA6/LDPE- g -GMA blends as compared with PA6/LDPE blends. The average diameter of dispersed polyolefin particles was about 0.4 ,m for LDPE- g -GMA contents <,50 wt.-%. A marked increase of melt viscosity was observed for the compatibilized blends depending on the concentration of grafted polyolefin, and it was accounted for by the reaction between the epoxy groups of GMA and the carboxyl/amine end-groups of PA6. The variation of torque was thus related to the molar ratio of reactive group concentration. The analysis of crystallization and melting behavior pointed out marked differences in the phase structure of the blends due to the presence of the functionalized polyolefin. Finally, the in situ formation of a graft copolymer between LDPE- g -GMA and PA6 was investigated by means of a selective dissolution method (Molau test) and by FT-IR and DSC analyses. SEM micrograph of fracture surface of PA6/LDPE- g -GMA 50/50 blend. [source]

Amphiphilic block copolymers of PtBA- b -PMMA as compatibilizers for blends of PET and PMMA

POLYMER ENGINEERING & SCIENCE, Issue 9 2006
B. Dewangan
PET and PMMA were blended at various weight fractions. These blends were compatibilized by employing amphiphilic block copolymers of PtBA- b -PMMA, having three compositions (1:3, 1:1, 3:1) and three weight fractions (3, 5, and 7 wt%) using a co-rotating twin screw extruder. The blends were evaluated for their mechanical, rheological, and morphological properties. Overall, the compatiblized blends showed improvement in properties compared with the properties of noncompatiblized blends. Mechanical properties of the compatibilized blends improved with an increase in the PMMA and compatibilizer weight fractions. It was observed that the compatibilizer with lower molecular weight and lower glass transition temperature, typically at 5 wt%, provided the overall best properties. POLYM. ENG. SCI. 46:1147,1152, 2006. © 2006 Society of Plastics Engineers. [source]

Effect of mixing protocol on compatibilized polymer blend morphology

POLYMER ENGINEERING & SCIENCE, Issue 5 2006
Bin Lin
We investigated the effect of mixing protocol on the morphology of compatibilized polymer blends made with premade compatibilizer and reactively formed in-situ compatibilizer in a custom-built miniature mixer Alberta Polymer Asymmetric Minimixer (APAM). The compatibilized blends show a finer morphology than uncompatibilized blends if the polymers are mixed together in the dry state and then fed into the mixer. It is found that premelting one polymer, and premixing polymers and compatibilizer, both greatly affect the compatibilized blends' morphology. The effects are complex since the dispersed phase particle size and distribution of the compatibilized blends may be smaller or larger when compared with the uncompatibilized system, depending on the material's physical and chemical properties; for example, diblock molecular weight or the preference of copolymer to migrate to a particular phase can change the final morphology. Good mobility of the copolymer to reach the interface is crucial to obtain a finer morphology. Micelles are observed when a high molecular weight diblock copolymer P(S- b -MMA) is used for a PS/PMMA blend. Because of its enhanced mobility, no micelles are found for a low molecular weight diblock copolymer P(S- b -MMA) in a PS/PMMA blend. For PS/PE/P(S- b -E) blends, finer morphology is obtained when P(S- b -E) is first precompounded with PS. Because the block copolymer prefers the PE phase, if the P(S- b -E) block copolymer is compounded with PE first, some remains inside the PE phase and does not compatibilize the interface. In the case of reactive blend PSOX/PEMA, premelting and holding the polymers at high temperature for 5 min decreases final dispersed phase particle size; however, premelting and holding for 10 min coarsens the morphology. POLYM. ENG. SCI. 46:691,702, 2006. © 2006 Society of Plastics Engineers. [source]

Compatibilizers based on polypropylene grafted with itaconic acid derivatives.

POLYMER ENGINEERING & SCIENCE, Issue 4 2003
Effect on polypropylene/polyethylene terephthalate blends
New types of compatibilizers based on functionalized polypropylene (PP) were synthesized by radical melt grafting either with monomethyl itaconate or dimethyl itaconate. The effect of these new modified PP compounds were tested as compatibilizers in PP/polyethylene terephthalate (PET) blends. Blends with compositions 15/85 and 30/70 by weight of PP and PET were prepared in a single-screw extruder. Morphology of the compatibilized blends revealed a very fine and uniform dispersion of the PP phase as compared with that of noncompatibilized blends of the same composition, leading to improved adhesion between the two phases. Whereas dimethyl itaconate derived agent showed less activity, the monomethyl itaconate parent compound showed an increase of the impact resistance of PET in PP/PET blend. This was attributed to the hydrophilic nature of the monomethyl itaconate part of this compatibilizer. The tensile strength of PET in noncompatibilized blends gradually decreases as the PP content increases, while blends containing functionalized PP exhibited higher values. [source]

Effect of epoxy functionalized compatibilizer on the mechanical properties of low-density polyethylene/plasticized tapioca starch blends

POLYMER INTERNATIONAL, Issue 12 2001
N Sailaja
Abstract A series of low-density polyethylene (LDPE) blends with varying proportions of plasticized tapioca starch have been used for the study of their mechanical properties. A functionalized epoxy resin, namely, poly(ethylene- co -glycidyl methacrylate) has been used as the compatibilizer. The impact and tensile properties have been measured by standard ASTM methods. The mechanical properties are seen to improve significantly with the addition of the epoxy compatibilizer, approaching values close to those of virgin LDPE. The scanning electron micrographs of the compatibilized blends show ductile failure which evidently contribute to improved mechanical properties. © 2001 Society of Chemical Industry [source]