We studied the morphological, mechanical, and rheological properties of polycarbonate (PC) and poly(acrylonitrile-butadiene-styrene) (PolyABS) blends with different types of compatibilizer. Styrene-acrylonitrile-maleic anhydride terpolymer (SAM) was used as a compatibilizer of the blends. For comparison, styrene-acrylonitrile-glycidyl methacrylate terpolymer (SAG) was also used as a compatibilizer. For the PC-PolyABS (70/30 wt %) blends with SAM, the mechanical strength and complex viscosity reached a maximum when the SAM concentration was 5 phr. The mechanical and rheological results of the blend were consistent with the morphological result that the PolyABS domain size reached a minimum when the SAM content was 5 phr. The interfacial tension (a) of the blend was compared with the compatibilizer type and content, which were calculated by the Palierne emulsion model with the relaxation time of the PC-PolyABS blend. The a is consistent with the morphological and mechanical properties of the PC-PolyABS blend. The results of the morphological, mechanical, and rheological properties of the blend suggest that SAM was a more effective compatibilizer than SAG, and the optimum compatibilizer content of SAM was 5 phr. V C 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46418.

Rigid polyurethane foams (PUFs) were prepared from polymeric 4,4Ј-diphenylmethane diisocyanate, polyester polyol, 1,4-butane diol, silicone surfactant, hydrochlorofluorocarbon (HCFC) 141B, and distilled water. The properties and structure of the PUFs were investigated with differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and a universal testing machine. The density of the PUF blown by distilled water and/or HCFC 141B decreased from 175.7 to 28.2 kg/m 3 with an increase of blowing agents. From the SEM results, the average cell size of the PUF blown by distilled water increased from 150 to 290 m with the distilled water content. From the DSC results, the glass-transition temperature (T g ) of the PUF blown by distilled water increased from 85.7 to 101.7°C with increasing distilled water content, whereas the T g of the PUF blown by HCFC 141B remained unchanged with HCFC 141B content. The compressive strength and modulus of the PUF blown by a mixture of distilled water and HCFC 141B was increased from 0.13 to 0.25 MPa and from 3.00 to 7.23 MPa, respectively, with the distilled water content at the sample density of about 44.0 kg/m 3 . The increase of the compressive strength and modulus of the PUF at the same density was related to the increase of the T g from 86.0 to 100.9°C.

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The sound absorption properties and airflow resistivity of polyurethane foams (PUFs) with multiwall carbon nanotube (MWCNT), perfluoroalkane (PFA), dimethylsiloxane (HMDS), and MWCNT/PFA hybrid additives were investigated with varying additive content. The results show the close relationship of the sound absorption coefficient and airflow resistivity, and increasing flow resistivity was found to improve the sound absorption coefficient of the PUF. For the PUF with MWCNT (at 0.50 phr)/PFA (at 1.25 phr) hybrid additives, the sound absorption coefficient and airflow resistivity were 0.80 (in the frequency range of 1,600–2,500 Hz) and 439,900 Ns/m4, respectively, which were the highest values among the investigated additive species and additive content. The sound absorption coefficient of the PUF with MWCNT (at 0.50 phr)/PFA (at 1.25 phr) was increased by 82.0% compared to that of the PUF without additives, probably because the PUF has the smallest cell size among the additive species and compositions investigated in this study. The results of the sound absorption coefficient, airflow resistivity, and cell size of the PUF suggest that to decrease the cell size and to increase the tortuous paths of the foams, MWCNT/PFA hybrid additives appeared to be the most effective additives and showed synergistic effects in the formation of PUF, and its small cell size increased the sound absorption properties of PUF. POLYM. COMPOS., 39:E1087–E1098, 2018. © 2017 Society of Plastics Engineers

The effect of carbon fiber (CF) modification with multiwall carbon nanotube (CNT) on the electrical, mechanical, and rheological properties of the polycarbonate (PC)/CF/CNT composite was investigated. The CF and multiwall CNT (MWCNT) were treated with sulfuric acid and nitric acid (3:1 wt %) mixture, to modify the CF with the CNT. For the PC with acid‐treated CNT (a‐CNT) modified acid‐treated CF (a‐CF) (PC/a‐CF/a‐CNT) composite, the electrical conductivity, and the electromagnetic interference shielding effectiveness (EMI SE) showed the highest values, compared with those of the PC/a‐CF and PC/a‐CF/CNT composites. The EMI SE of the PC/a‐CF (10 wt %)/a‐CNT (0.5 wt %) composite was found to be 26 (dB at the frequency of 10.0 GHz, and the EMI SE was increased by 91.2%, compared to that of the PC/a‐CF composite at the same amount of total filler content. Among the composites studied in this work, the PC/a‐CF/a‐CNT composite also showed the highest values of relative permittivity (εr) and dielectric loss factor. The above results suggest that the CF modification with the a‐CNT significantly affected the electrical conductivity and EMI SE of the composite, and the hybrid fillers of the a‐CNT and a‐CF resulted in good electrical pathways in the PC/a‐CF/a‐CNT composite. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47302.

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