The influence of the arrangement of styrene in methyl methacrylate/butadiene/styrene on the properties of PMMA/SAN/MBS blends

A series of methyl methacrylate‐butadiene‐styrene (MBS) core–shell impact modifiers were prepared by grafting styrene (St) and methyl methacrylate (MMA) onto polybutadiene (PB) or styrene‐butadiene rubber (SBR) seed latex in emulsion polymerization. All the MBS modifiers were designed to have the same total chemical composition, and Bd/St/MMA equaled 39/31/30, which was a prerequisite for producing transparent blends with poly(MMA)/styrene‐acrylonitrile (PMMA/SAN) matrix copolymers. Under this composition, different ways of arrangement for styrene in MBS led to the different structure of MBS modifier. The concentration of PB or SBR rubber of MBS in PMMA/SAN/MBS blends was kept at a constant value of 15 wt.%. The effects of arrangement of St in MBS on the mechanical and optical properties of PMMA/SAN/MBS blends were investigated. The results indicated that Izod impact strength of PMMMA/SAN/MBS blend with the amount of St grafted on core in MBS was higher than that of blend with the amount of St copolymerized with Bd in core of MBS, while the transparency of blend is opposite. From transmission electron microscopy, it was found that the arrangement of St in MBS influenced the dispersion of blend, which led to different toughness. Copyright © 2013 John Wiley & Sons, Ltd.     

Effects of methyl methacrylate grafting and in situ silica particle formation on the morphology and mechanical properties of natural rubber composite films

The effects of methyl methacrylate (MMA) grafting and in situ formation of silica particles on the morphology and mechanical properties of natural rubber latex (NRL) were investigated. MMA grafting on NRL was carried out using cumyl hydroxy peroxide/tetraethylene pentamine (CHPO/TEPA) as a redox initiator couple. The grafting efficiency of the grafted NR was determined by solvent extractions and the grafted NRL was then mixed with tetraethoxysilane (TEOS), a precursor of silica, coated by adherence to a glass surface to form a film and cured at 80°C. The resultant products were characterized by FT‐IR and transmission electron microscopy. The influence of varying the MMA monomer weight ratio on the surface morphology of the composites was investigated by scanning electron and atomic force microscopy. The PMMA (poly MMA) grafted NRL particles were obtained as a core/shell structure from which the NR particles were the core seed and PMMA was a shell layer. The silane was converted into silica particles by a sol–gel process which was induced during film drying at 80°C. The silica particles were fairly evenly distributed in the ungrafted NR matrix but were agglomerated in the grafted NR matrix. The root‐mean‐square roughness increased with an increasing weight ratio of MMA in the rubber. The in situ silica particles in the grafted NR matrix slightly increased both the modulus and the tear strength of the composite film. Copyright © 2008 John Wiley & Sons, Ltd.     

Superior heat‐resistant and oil‐resistant blends based on dynamically vulcanized hydrogenated acrylonitrile butadiene rubber and polyamide 12

High‐performance thermoplastic vulcanizates (TPVs) are the new generation of TPVs that provide superior heat and oil aging behavior. TPVs based on hydrogenated acrylonitrile butadiene rubber and polyamide 12 (PA12) have been first developed by the dynamic vulcanization process, in which selective cross‐linking of the elastomer phase during melt mixing with the thermoplastic phase (PA12) was carried out simultaneously. In this present investigation, hydrogenated acrylonitrile butadiene rubber (HNBR)/PA12 and partially hydrogenated carboxylated acrylonitrile butadiene rubber (XHNBR)/PA12 with blend ratio of 50:50, 60:40, and 70:30 wt% were prepared at 185°C at a rotor speed of 80 rpm for 5 min. Di‐(2‐tert‐butyl peroxy isopropyl) benzene was chosen as the suitable cross‐linking peroxide to pursue the dynamic vulcanization. TPV based on 50:50 HNBR/PA12 and XHNBR/PA12 show better physico‐mechanical properties, rheological behavior, thermal stability, dynamic mechanical analysis, and creep behavior among all the TPVs. Morphology study reveals that dispersed phase morphology has been formed with an average dimension of the rubber particles in the range of 0.8–1.5 µm. For aging test, TPVs were exposed to air and ASTM oil 3, respectively. Air aging tests were carried out in hot air oven for 72 hr at 125°C, while the oil aging tests were carried out after immersion of the samples into the oils in an aging oven. After aging, there is only slight deterioration in the physico‐mechanical properties of the TPVs. In case of 50:50 blends of HNBR/PA12 and XHNBR/PA12, the retention of the properties upon after aging was found excellent. These TPVs are designed to find potential application in automotive sector especially for under‐hood‐application, where high‐temperature resistance as well as high oil resistance is of prime importance. Copyright © 2016 John Wiley & Sons, Ltd.     

Structure–property relationships in modified natural rubber latexes grafted with methyl methacrylate and vinyl neo‐decanoate

A series of modified natural rubber latexes (NRLs) grafted with poly(methyl methacrylate) (PMMA) were prepared by seeded emulsion polymerization with NRL as the seed polymer. Two different redox systems, cumene hydroperoxide (CHP)/tetraethylene pentamine (TEPA) and tert‐butyl hydroperoxide (t‐BHP)/TEPA, were used to initiate polymerization, and phase mixing was promoted by the addition of vinyl neo‐decanoate (VneoD). The CHP/TEPA system was more efficient than t‐BHP/TEPA for the grafting of secondary polymers in modified natural rubber (NR). The enhanced phase mixing in the presence of VneoD was attributed to the solubility parameter of the VneoD‐rich methyl methacrylate–VneoD copolymer formed late in the reaction, lying between that of PMMA and NR, and the extent to which this polymer was grafted to the NR backbone. The viscoelastic properties of the polymers were investigated as a function of composition, temperature, and frequency; changes in viscoelastic behavior consistent with the presence of a high‐T_g PMMA phase (where T_g is the glass‐transition temperature) were observed. This suggested a degree of phase mixing that increased with increasing VneoD content and increasing flux of oxygen‐centered radicals within the NR particles. More phase mixing resulted in poorer film formation, which was consistent with the localization of a high‐T_g secondary polymer phase near the particle surface. The apparent concentration of PMMA near the surface of the particles was also observed with transmission electron microscopy. The localization of PMMA near the particle surfaces was consistent with the presumed locus of radical generation in these systems: the redox couple used to initiate the polymerization consisted of an oil‐soluble hydroperoxide and a water‐soluble amine that reacted predominantly at the water/particle interface. The viscoelastic properties of the modified NRLs that were prepared suggest that these synthetic procedures provide a means of controlling phase mixing and branching, such as for improving the suitability of these modified rubbers in pressure‐sensitive‐adhesive formulations. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 809–822, 2002; DOI 10.1002/pola.10165     

Influence of elastomeric core–shell impact modifiers on mechanical properties of cellulose diacetate resin

Cellulose diacetate (CDA) plasticized with triacetine was blended by melting extrusion with two different kind of elastomeric core–shell impact modifiers: methyl methacrylate (MMA, shell) grafted onto styrene–butadiene–rubber (SBR, core) (MSBR) and MMA (shell) grafted onto butyl acrylate rubber (BAR, core) (MBAR). The different CDA/MSBR and CDA/MBAR blends were characterized by mechanical properties and morphological observation with various impact modifier contents. The highest impact strength was observed in the case of the blend with 5 wt% of MSBR and 3 wt% of MBAR, respectively. The tensile strength and Young’s modulus of CDA blends were decreased with increasing both MSBR and MBAR. According to SEM observation, MBAR was dispersed more effectively in CDA matrix than that of MSBR, thus indicating improved impact strength.     

Dynamically cured natural rubber/EVA blends: influence of NR‐g‐poly(dimethyl (methacryloyloxymethyl)phosphonate) compatibilizer

Graft copolymer of natural rubber and poly(dimethyl(methacryloyloxymethyl)phosphonate) (NR‐g‐PDMMMP) was prepared in latex medium via photopolymerization. It was then used to promote the blend compatibility of dynamically cured 40/60 natural rubber (NR)/ethylene vinylacetate copolymer (EVA) blends using various loading levels at 1, 3, 5, 7, 9, 12, and 15 wt%. It was found that the increasing loading levels of NR‐g‐PDMMMP in the blends caused the increasing elastic modulus and complex viscosity until reaching the maximum values at a loading level of 9 wt%. The properties thereafter decreased with the increasing loading levels of NR‐g‐PDMMMP higher than 9 wt%. The smallest vulcanized rubber particles dispersed in the EVA matrix with the lowest tan δ value was also observed at a loading level of 9 wt%. Furthermore, the highest tensile strength and elongation at break (i.e., 17.06 MPa and 660%) as well as the lowest tension set value (i.e., 27%) were also observed in the blend using this loading level of the compatibilizer. Addition of NR‐g‐PDMMMP in the dynamically cured NR/EVA blends also improved the thermal stability of the blend. That is, the decomposition temperature increased with the addition of the graft copolymer. However, the addition of NR‐g‐PDMMMP in the blends caused the decreasing degree of crystallinity of the EVA phase in the blend. However, the strength properties of the blend are still high because of the compatibilizing effect. Copyright © 2009 John Wiley & Sons, Ltd.     

Studies on radiation grafting of methyl methacrylate onto natural rubber for improving modulus of latex film

Methyl methacrylate (MMA) can be grafted onto natural rubber (NR) in latex by gamma irradiation for improving the mechanical properties of the dry films. Physical blending of MMA-grafted NR latex with radiation vulcanized natural rubber latex (RVNRL) or simultaneous radiation grafting and crosslinking are found to be useful techniques for improving the properties of latex films. Moduli of the films are improved with increasing MMA content; however, tensile strength is reduced. High modulus without much reduction in tensile strength can be achieved if the MMA content is 50–60 parts per hundred rubber.     

Improving properties of natural rubber/polyamide 12 blends through grafting of diacetone acrylamide functional group

The aim of the present study was to improve the compatibility in blends of natural rubber (NR) and polyamide 12 (PA12) by grafting NR with hydrophilic monomer, diacetone acrylamide (DAAM), via seeded emulsion polymerization. The increase in polarity of NR after grafting modification was confirmed by a considerable increase in the polar component of its surface energy. Blends of graft copolymers of NR and poly(diacetone acrylamide) prepared using 10 wt% of DAAM (NR‐g‐PDAAM10) and PA12 were prepared at a 60/40 blend ratio (wt%) using simple blend and dynamic vulcanization techniques. The mechanical and rheological properties of the resulting blends were subsequently investigated and compared with those of the corresponding blends based on unmodified NR. The results show that dynamic vulcanization led to a significant increase in both mechanical and rheological properties of the blends. It was also observed that the dynamically cured NR‐g‐PDAAM10/PA12 blend had smaller particle size of vulcanized rubber dispersed in the PA12 matrix than observed for the dynamically cured NR/PA12 blend. This is due to the compatibilizing effect of DAAM groups present in NR‐g‐PDAAM10 molecule, which decreases the interfacial tension between the two polymeric phases. Therefore, it can be stated that the interfacial adhesion between NR and PA12 was improved by the presence of DAAM groups in NR molecule. This was reflected in the higher tensile properties observed in the dynamically cured NR‐g‐PDAAM10/PA12 blend. Copyright © 2017 John Wiley & Sons, Ltd.     

Compatibilizing effect of a graft copolymer on bacterial poly(3‐hydroxybutyrate)/poly(methyl methacrylate) blends

Blends of isotactic (natural) poly(3‐hydroxybutyrate) (PHB) and poly(methyl methacrylate) (PMMA) are partially miscible, and PHB in excess of 20 wt % segregates as a partially crystalline pure phase. Copolymers containing atactic PHB chains grafted onto a PMMA backbone are used to compatibilize phase‐separated PHB/PMMA blends. Two poly(methyl methacrylate‐g‐hydroxybutyrate) [P(MMA‐g‐HB)] copolymers with different grafting densities and the same length of the grafted chain have been investigated. The copolymer with higher grafting density, containing 67 mol % hydroxybutyrate units, has a beneficial effect on the mechanical properties of PHB/PMMA blends with 30–50% PHB content, which show a remarkable increase in ductility. The main effect of copolymer addition is the inhibition of PHB crystallization. No compatibilizing effect on PHB/PMMA blends with PHB contents higher than 50% is observed with various amounts of P(MMA‐g‐HB) copolymer. In these blends, the graft copolymer is not able to prevent PHB crystallization, and the ternary PHB/PMMA/P(MMA‐g‐HB) blends remain crystalline and brittle. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1390–1399, 2002     

Synthesis of a novel phosphate‐containing highly transparent PMMA copolymer with enhanced thermal and flame retardant properties

A novel poly(methyl methacrylate) (PMMA)‐based copolymer (PMMA‐co‐BDPA) rich in aromatic rings was synthesized via radical copolymerization between a phosphorus‐containing acrylic monomer (BDPA) and methyl methacrylate (MMA). UV‐vis spectroscopy demonstrated that the copolymer had high transparency. Thermogravimetric analysis (TGA) and a differential scanning calorimeter (DSC) were used to test the thermal properties of the composites. Additionally, the PMMA‐co‐BDPA‐15 copolymer exhibited a 23% increase in the limited oxygen index (LOI) value. A cone calorimeter test indicated that the peak heat release rate (pk‐HRR) of PMMA‐co‐BDPA was reduced by 29.2% compared with that of pure PMMA, and the carbon yield of burning was obviously increased. The combined test results demonstrated that the prepared copolymer material had good transparency, thermal stability, and flame retardancy.     

The mechanical properties of radiation-vulcanized NR/BR blending system

The effect of radiation dose on the mechanical properties of NR/BR blending system is reported in this paper. A comparison was made between sulphur vulcanization and radiation vulcanization for an optimal nature rubber (NR)/ butyl rubber (BR) blending ratio (60/40) at dose range from 10 to 150 kGy. The result shows that the mechanical properties, especially, tensile strength, elongation at break, and tear strength have been improved significantly by radiation–vulcanization. This finding was also proved by thermal aging experiment on a selected NR/BR blend at 70°C for up to 168 h.     

Preparation of polypropylene/ethylene‐propylene‐diene terpolymer/nitrile rubber ternary thermoplastics vulcanizates with good mechanical properties and oil resistance by core‐shell dynamic vulcanization

As the most successful commercialized thermoplastic vulcanizates (TPVs), polypropylene (PP)/ethylene propylene rubber (EPDM) TPVs exhibit poor oil resistance. In this work, we prepared PP/EPDM/butadiene acrylonitrile rubber (NBR) ternary TPVs with good oil resistance using core‐shell dynamic vulcanization. According to the theoretical analysis of the spreading coefficient and the transmission electron microscopy results, the rubber phases exhibited a special core‐shell structure, in which the cross‐linkedNBR‐core was encapsulated by the EPDM‐shell. The core‐shell structure effectively improved the interfacial compatibility between PP and NBR phase as the EPDM‐shell could avoid the direct contact of them, thus improving the mechanical properties of the TPVs. For example, the PP/EPDM/NBR (40/30/30) ternary TPV showed enhanced tensile strength of 12.57 MPa, compared with 10.71 MPa of PP/EPDM (40/60) TPV and 11.11 MPa of PP/NBR (40/60) TPV, respectively. Moreover, the oil resistance of the TPVs was also improved. Compared with PP/EPDM TPV, the change rates in mass, volume, tensile strength and elongation at break of PP/EPDM/NBR TPV after oil immersion decreased by 42.18%, 48.69%, 52.68% and 28.77%, respectively.     

Thermoplastic elastomer based on high‐density polyethylene/natural rubber blends: rheological,thermal, and morphological properties

Thermoplastic elastomer (TPE) comprising air‐dried sheet or natural rubber (ADS or NR) and high‐density polyethylene (HDPE) was prepared by a simple blending technique. NR and HDPE were mixed with each type of phenolic compatibilizer (HRJ‐10518 or SP‐1045) or liquid natural rubber (LNR) at 180°C in an internal mixer. The mixing torque, shear stress, and shear viscosity of the blends increased with increasing amounts of NR. Positive deviation blend (PDB) for the blends containing active hydroxyl methyl phenolic resin in HRJ‐10518 or dimethyl phenolic resin in SP‐1045 was obtained. PDB was not observed for the blends without the compatibilizers or with LNR. The blends with HRJ‐10518 or SP‐1045 were compatible or partially compatible while the LNR blends were incompatible. In the phenolic compatibilized blends, NR dispersed in the HDPE matrix was found in the NR/HDPE blends of 20/80, 40/60, and 50/50 ratios. HDPE dispersed in NR matrix was obtained in the NR/HDPE blend of 80/20 ratio, and the co‐continuous phase was accomplished in the NR/HDPE blend of 60/40 ratio. The NR/HDPE blend at 60/40 ratio compatibilized with HRJ‐10518 and fabricated by a simple plastic injection molding machine exhibited higher ultimate tensile strength and elongation at break (EB). Incorporation of parafinic oil caused a decreasing tendency in tensile strength with increases in EB. The TPNRs exhibited high elastomeric nature with low‐tension set. Copyright © 2007 John Wiley & Sons, Ltd.     

Surface modification of natural rubber film by polymerisation of methyl methacrylate in water-based system

Polymerisation of methyl methacrylate (MMA) on the surface of natural rubber (NR) film was studied in order to increase the surface hardness, roughness and, hence, to decrease the friction coefficient of rubber. We used the two-step process: (i) swelling of MMA and tert-butyl hydroperoxide, emulsified in an aqueous solution of sodium dodecyl sulphate, onto the NR film surface, and (ii) subsequently immersing the swollen rubber strip into an alkaline aqueous solution of ferrous ion/fructose for redox initiation. The presence of PMMA on the NR surface was examined by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). Increasing the concentration of ferrous ion caused an increase in MMA conversion. The surface morphology observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM) in tapping mode revealed the aggregation of micronmetre-scale nodules on the modified surface. The surface hardness and roughness increased with increasing PMMA content.     

STUDY ON THE PROPERTIES OF BLEND OF NATURAL RUBBER LATEX/METHYL METHACRYLATE GRAFTED RUBBER LATEX BY GAMMA RADIATION

Natural rubber latex(NRL)and methyl methacrylate(MMA)grafted rubber latex were blended in different ratios and irradiated at various absorbed doses by gamma rays from Co-60 source at room temperature.The tensile properties, swelling ratio and permanent set were measured.The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of 8 kGy.Modulus increases from 6.99 MPa to 9.87 MPa for an increase in proportion of MMA grafted rubber from 40% to 60% in the blend at similar absorbed dose.Elongation at break and swelling ratio decrease with increasing absorbed dose as well as the MMA grafted rubber content in the blends.The decreasing trend of permanent set is high up to 5 kGy absorbed dose,and beyond that dose,it becomes almost flat.     

Polyamide 66/EPR‐g‐MA blends: mechanical modeling and kinetic analysis of thermal degradation

The present investigation deals with the mechanical, thermal, and morphological properties of binary nylon 66/maleic anhydride grafted ethylene propylene rubber (EPR‐g‐MA) blends at different dispersed phase (EPR‐g‐MA) concentrations. The effects of EPR‐g‐MA concentration and dispersed particle size on the mechanical properties of the blends were studied. Analysis of the tensile data in terms of various theoretical models revealed the variation of stress concentration effect with blend composition and the improvement of interfacial adhesion between dispersed rubber phase and nylon 66 matrix. The thermal degradation of the blends was analyzed by nonisothermal thermogravimetric analysis (TGA). It was found that the activation energy (E_a) and overall reaction order of thermal degradation decreased with increasing EPR‐g‐MA content. The scanning electron microscopic (SEM) analysis showed a significant decrease in dispersed particle size with increasing EPR‐g‐MA content, which was explained on the basis of the level of chemical interaction (in situ compatibilization) between nylon 66 and EPR‐g‐MA. The surface morphology of the nylon 66/EPR‐g‐MA blends was illustrated by the roughness of atomic force microscopy (AFM) images. Copyright © 2008 John Wiley & Sons, Ltd.     

Preparation and properties of novel fluorosilicone thermoplastic vulcanizate with cross‐linking–controlled core‐shell structure

A new fluorosilicone thermoplastic vulcanizate (TPV) composed of poly(vinylidene fluoride) (PVDF), silicone rubber (SR), and fluororubber (FKM) was successfully prepared through dynamic vulcanization. The morphological structure of the TPVs had core‐shell elastomer particles dispersed in a continuous PVDF matrix. Furthermore, the cross‐linking of core‐shell structure was controlled by adopting different curing agent. The effect of cross‐linking–controlled core‐shell structure on the morphology, crystallization behavior, stress relaxation test, solvent‐resistant properties of the obtained TPVs were investigated. It was found that the shell cross‐link had a significant influence on the crystallinity of the PVDF phase. The core‐shell bicross‐linked TPV was found to provide the lowest rate of relaxation. An obvious stress softening phenomenon was observed in the uniaxial loading‐unloading cycles in tension. The bicross‐linked TPV had good solvent resistant properties. The tensile strength of the bicross‐linked TPV was still 12 MPa even after immersed in butyl acetate for 48 hours.     

Synthesis and characterization of poly(methyl methacrylate)/casein nanoparticles with a well‐defined core‐shell structure

Well‐defined, core‐shell poly(methyl methacrylate) (PMMA)/casein nanoparticles, ranging from 80 to 130 nm in diameter, were prepared via a direct graft copolymerization of methyl methacrylate (MMA) from casein. The polymerization was induced by a small amount of alkyl hydroperoxide (ROOH) in water at 80 °C. Free radicals on the amino groups of casein and alkoxy radicals were generated concurrently, which initiated the graft copolymerization and homopolymerization of MMA, respectively. The presence of casein micelles promoted the emulsion polymerization of the monomer and provided particle stability. The conversion and grafting efficiency of the monomer strongly depended on the type of radical initiator, ROOH concentration, casein to MMA ratio, and reaction temperature. The graft copolymers and homopolymer of PMMA were isolated and characterized with Fourier transform infrared spectroscopy and differential scanning calorimetry. The molecular weight determination of both the grafted and homopolymer of PMMA suggested that the graft copolymerization and homopolymerization of MMA proceeded at a similar rate. The transmission electron microscopic image of the nanoparticles clearly showed a well‐defined core‐shell morphology, where PMMA cores were coated with casein shells. The casein shells were further confirmed with a zeta‐potential measurement. Finally, this synthetic method allowed us to prepare PMMA/casein nanoparticles with a solid content of up to 31%. Thus, our new process is commercially viable. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3346–3353, 2003     

Novel fluorosilicone thermoplastic vulcanizates prepared via core‐shell dynamic vulcanization: Effect of fluororubber/silicone rubber ratio on morphology,crystallization behavior,and mechanical properties

Recently, we have reported a novel core‐shell dynamic vulcanization method to prepare poly(vinylidene fluoride) (PVDF)/fluororubber (FKM)/silicone rubber (SR) thermoplastic vulcanizates (TPVs) with cross‐linked rubber core‐shell particles. However, the shell thickness on the properties has not been studied in detail. Herein, these PVDF‐based TPVs different FKM‐shell thickness were prepared by changing FKM/SR ratios. The effect of FKM‐shell/SR‐core ratio on morphology, crystallization, and mechanical properties of the ternary TPVs was studied. The results showed that the FKM shell had more positive effect on interfacial‐induced crystallization behavior than the SR core due to its better compatibility with PVDF. When the FKM/SR ratio was <1, FKM was not enough to encapsulate SR completely, which resulted in the formation of imperfect core‐shell structure. However, when the FKM/SR ratio was >1, perfect core‐shell structure was formed. Therefore, the mechanical properties improved with increasing FKM content; especially, a remarkable improvement was observed when FKM/SR ratio was >1. This study could provide more information for the design of TPVs with core‐shell structure.     

Dynamic vulcanization of reclaimed tire rubber and high density polyethylene blends

Dynamic vulcanization of reclaimed tire rubber (RTR) and HDPE blends was reported. The effect of blend ratio, methods of vulcanization, i.e. sulphur, peroxide, and mixed system and the addition of compatibilizer on mechanical, thermal, and rheological properties were investigated. The blend with highest impact strength was obtained from 50/50 RTR/HDPE vulcanized by sulphur. Increasing the RTR content to more than 50% resulted in a decrease in the impact strength of blend, most likely due to the increasing carbon black content. For tensile strength, the presence of rubber and carbon black, however, unavoidably caused a drop in this property. Comparing among three methods of vulcanization, sulphur system seems to be the most effective method. Results from solvent swelling ratio, glass transition temperatures and viscosity indicated that the sulphur vulcanization created the highest degree of cross-link and filler-matrix interaction in the RTR/HDPE blend. Morphology of the blends was also assessed by scanning electron microscopy (SEM).