In the present research, poly(acrylonitrile-butadienestyrene)/polycarbonate (ABS/PC) blends were prepared in a twin screw extruder. An attempt to reinforce and promote compatibility of the above systems was made by the incorporation of organically modified montmorillonite (OMMT, Cloisite 30B), as well as by the addition of compatibilizer (ABS grafted with maleic anhydride, ABS-g-MAH), and the effect of those treatments on the morphology, thermal transitions, rheological, and mechanical properties of the above blends was evaluated. The addition of compatibilizer in ABS/PC blends does not significantly affect the glass transition temperature (T g ) of SAN and PC phases, whereas the incorporation of Cloisite 30B decreases slightly the T g values of SAN and, more significantly, that of PC in compatibilized and uncompatibilized blends. The T g of PB phase remains almost unaffected in all the examined systems. The obtained results suggest partial dissolution of the polymeric components of the blend and, therefore, a modified Fox equation was used to assess the amount of PC dissolved in the SAN phase of ABS and vice versa.Reinforcing with OMMT enhances the miscibility of ABS and PC phases in ABS/PC blends and gives the best performance in terms of tensile strength, modulus of elasticity, and storage modulus, especially in 50/50 (w/w) ABS/PC blends. The addition of ABS-g-MAH compatibilizer, despite the improvement of intercalation process in organoclay/ ABS/PC nanocomposites, did not seem to have any substantial effect on the mechanical properties of the examined blends. POLYM. COMPOS., 35:1395-1407, 2014

In this research, graphene nanocomposites of poly(acrylonitrile‐butadiene‐styrene)/polycarbonate (ABS/PC) and ABS/polypropylene (ABS/PP) blends were prepared by melt blending and their thermal and mechanical properties were studied. The incorporation of graphene into ABS/PC and ABS/PP blends caused a significant decrease of their melt flow index values. Although graphene led to reduction of onset degradation temperature (Tonset) and maximum degradation rate temperature (Tpeak) of ABS/PC blends, and mainly of pure PC, the obtained residue from thermogravimetric analysis showed an increase. The thermal degradation of PC phase, in PC‐rich blends, was completed at higher temperatures. In ABS/PP blends, the effect of graphene was an outstanding increase of Tonset and Tpeak in the case of pure PP, while increasing the residue at all proportions. Regarding the Young's modulus, in ABS/PC blends the result of the addition of graphene was dependent on the blend composition. In ABS/PP hybrids, the elastic modulus increased by the incorporation of graphene and this increase, reached anabout 43% in pure PP. The addition of graphene to pure ABS, pure PP and their blend 50/50 w/w resulted in an increasing trend of the dielectric constant (κ′), whereas the loss factor (tanδ) was similar in non‐reinforced and graphene‐reinforced samples, within the entire range of the examined frequencies. POLYM. COMPOS., 40:E1662–E1672, 2019. © 2018 Society of Plastics Engineers

In the present research polypropylene/expanded graphite (PP/ExpG) and polypropylene/graphene nanoplatelet (PP/GNP) composites were prepared by melt blending and their morphology and tensile properties were investigated. Although both reinforcements improved the elastic modulus of PP, PP/GNP composite presented better dispersion of the nanofiller in the polymer matrix and it was selected for further re-extrusion and ageing experiments. The re-extrusion affected the content of crystal phases of PP in pure PP and in its nanocomposite with GNP and increased their elastic modulus. The ageing of one and five times re-extruded PP caused an increase of the -crystal phase and the formation of voids in the cross-section. GNPs seem to protect the PP matrix from ageing as in Fourier transform IR spectra of PP/GNP nanocomposite, both one and five times extruded, the peak corresponding to carbonyl degradation products of PP was barely visible. The tensile properties of aged nanocomposites, one and five times re-extruded, were similar to those of the corresponding non-aged composites, whereas in aged PP the tensile strength and strain decreased significantly compared to non-aged PP. The anti-ageing effect of graphene can prolong the life of the PP matrix.

The effect of incorporation of clay nanoparticles on the vulcanization reaction of silanol-terminated polysiloxane was studied. Three different types of commercial clays were investigated as reinforcement, namely: Cloisite 20 A (organically modified with nonpolar aliphatic chains), Cloisite 30B (modified with aliphatic chains containing hydroxyl-end groups) and Nanofil 116, an unmodified montmorillonite as a reference. Nanoclays were found to increase the rate of curing, assessed by viscosity measurements, in all the examined systems and the acceleration rate is proportional to the content of the additive. Moreover, an increase of the area of peaks corresponding to the formation of SiAOASi bonds (900-1200 cm 21) was recorded by FTIR spectroscopy for pure and reinforced poly(dimethylsiloxane) (PDMS). Temperature modulated differential scanning calorimetry was also used for accurately monitoring the curing reaction of organoclay/PDMS hybrids, through the heat capacity and the enthalpy of cold crystallization measurements. For pure PDMS low reaction rate was observed during the first 200 min, followed by fast acceleration. A linear increase of the reaction rate as a function of time was observed for the organoclay/PDMS hybrids. POLYM. ENG. SCI., 55:957-965, 2015.

In this study, poly(acrylonitrile-butadiene-styrene)/polypropylene (ABS/PP) blends with various compositions were prepared by melt intercalation in a twin-screw extruder. Modifications of the above blends were performed by using organically modified montmorillonite (OMMT, Cloisite 30B) reinforcement as well as two types of compatibilizers, namely polypropylene grafted with maleic anhydride (PP-g-MAH) and ABS grafted with maleic anhydride (ABS-g-MAH). Increasing the PP content in ABS matrix seems to increase the melt flow and thermal stability of their blends, whereas a deterioration of the tensile properties was recorded. On the other hand, the addition of ABS to PP promotes the formation of the b-crystalline phase, which became maximum at 30 wt% ABS concentration, and increases the crystallization temperature (T c ) of PP. A tendency for increase of T c was also recorded by incorporation of the above compatibilizers, whereas the glass transition temperature (T g ) of PP and SAN phase in ABS was reduced. Regarding the Young's modulus, the greatest improvement was observed in pure ABS/PP blends containing organically modified nanoclay. However, in reinforced pure PP, the use of compatibilizers is recommended in order to improve the elastic modulus. The addition of OMMT to noncompatibilized and compatibilized ABS/PP blends significantly improves their storage modulus. POLYM. ENG. SCI., 56:458-468, 2016.