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Liu H.-D.,Sichuan University | Liu Z.-Y.,Sichuan University | Yang M.-B.,Sichuan University | He Q.,China Bluestar Chengrand Chemical Co.
Journal of Applied Polymer Science

Graphene with amine group was covalently grafted on the polyurethane foam with nitrile group to form superhydrophobic foam. Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), thermogravimetric analysis (TGA), optical contact angle measuring device, and scanning electron microscopy (SEM) were used to characterize the foam, showing the dodecane diamine was successfully grafted onto graphene oxide and the graphene oxide modified by dodecane diamine was successfully grafted onto polyurethane foam. Moreover, the modified foam exhibited a high contact angle (159.1 ± 2.3°) compared to unmodified foam (121.4 ± 3.2°). And that is due to the foam modified by amidation of graphene oxide can enhance the surface roughness and reduce the surface energy of the foam. Owing to modified foam was extremely hydrophobic and preferentially adsorbed oil other than water, the sorption capacity of the modified foam for toluene, gasoline, and diesel is 41, 27, and 26 g/g, respectively. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3530-3536, 2013 Copyright © 2013 Wiley Periodicals, Inc. Source

Chen W.,Sichuan University | Fu X.,China Bluestar Chengrand Chemical Co. | Ge W.,Sichuan University | Xu J.,Sichuan University | Jiang M.,Sichuan University
Polymer Degradation and Stability

Bisneopentyl glycol dithiopyrophosphate (DDPS) has been successfully microencapsulated with melamine formaldehyde (MF) resin as a shell material by in-situ polymerization process in this study. Chemical structures of DDPS and microencapsulated DDPS (MDDPS) were characterized by Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Morphologies were investigated by scanning electron microscopy (SEM), while particle size and distribution were investigated by granulometry. The results show that microencapsulation can make DDPS particles be coated by MF resin entirely. After microencapsulation, the mean diameter of DDPS increased slightly from 1.405 μm to 2.757 μm, DDPS and MDDPS both were applied in polyvinyl alcohol (PVA) films to compare their flame retardancy. The flame retardation property was evaluated by limiting oxygen index (LOI). Decomposition mechanism was investigated by TG-FTIR, FTIR and SEM. The results indicated that MDDPS has better flame retardancy to PVA, and the LOI of MDDPS/PVA composite is 31.8%. As a fire retardant for PVA, DDPS mainly functions in the gaseous phase rather than in the condensed phase, while MDDPS works in both the gaseous and condensed phase. © 2014 Elsevier Ltd. All rights reserved. Source

Huang J.,Sichuan University | Zhang Y.,China Bluestar Chengrand Chemical Co. | Yang Q.,Sichuan University | Yang Q.,University of Sichuan | And 4 more authors.
Journal of Applied Polymer Science

A novel halogen-free charring agent bi(4-methoxy-1-phospha-2, 6, 7-trioxabicyclo [2.2.2]-octane-1-sulfide) phenylphosphate (BSPPO) was synthesized from phenylphosphonic dichloride (PPDC), and 4-hydroxymethyl-1- phospha-2, 6, 7-trioxabicyclo[2.2.2]-octane-1-sulfide (SPEPA) which was synthesized from pentaerythritol and thiophosphoryl chloride in this article. The structure of BSPPO and SPEPA was characterized by Fourier transform infrared (FTIR), 1H-NMR, 13C-NMR, and 31P-NMR. Combined with ammonium polyphosphate (APP) and melamine pyrophosphate (MPP), the flame retardance and dripping resistance of BSPPO added in polypropylene (PP) were investigated. The fire performance of the flame retardant PP system was investigated by limiting oxygen index (LOI), vertical burning test (UL-94), and cone calorimeter. The thermal stabilities of the composites were studied by thermogravimetric analysis (TGA). The flame retardance mechanism was investigated by FTIR and scanning electronic micrograph (SEM). The mechanical properties and water solubility were also investigated. The residue of BSPPO is 40.6% at 600°C, which indicates BSPPO has excellent charring ability. The char residue of the polypropylene intumescent flame retardant (PP-IFR) system is 22% at 600°C, which suggests that the flame retardation synergy of APP, BSPPO, and MPP is good. With the optimum formulation, the LOI of the IFR-PP system is 32.0, and the UL-94 is V-0 rating. The heat release rate (HRR), total heat release (THR), smoke production rate (SPR), total smoke production (TSP), and mass loss rate (MLR) of IFR-PP with the optimum formulation decrease significantly comparing to pure PP from cone calorimeter analysis. The FTIR and SEM results indicate that the char properties and the char yield have direct effect on the flame retardance and antidripping behaviors. © 2011 Wiley Periodicals, Inc. Source

He Y.-L.,Sichuan University | Guo Y.-L.,Sichuan University | He R.,Sichuan University | Jin T.-X.,Sichuan University | And 4 more authors.
Chinese Journal of Polymer Science (English Edition)

Poly(bisphenol A carbonate) (BPA-PC) was post-polymerized by solid-state polymerization (SSP) after supercritical CO2-induced crystallization in low molecular weight particles prepolymerized via melt transesterification reaction. The effects of the crystallization conditions on melting behavior and SSP of BPA-PC were investigated with differential scanning calorimetry (DSC), Ubbelohde viscosity method and gel permeation chromatography (GPC). The reaction kinetics of the SSP of crystallized prepolymers was studied as a function of reaction temperatures for various reaction periods. As a result, the viscosity average molecular weight of BPA-PC particles (2 mm) increased from 1.9 × 104 g/mol to 2.8 × 104 g/mol after SSP. More importantly, the significantly enhanced thermal stability and mechanical properties of solid-state polymerized BPA-PC, compared with those of melt transesterification polymerized BPA-PC with the same molecular weight, can be ascribed to the substantial avoidance of undergoing high temperature during polymerization. Our work provides a useful method to obtain practical product of BPA-PC with high quality and high molecular weight. © 2015, Chinese Chemical Society, Institute of Chemistry, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg. Source

Cai R.-Q.,Sichuan University | Peng T.,Sichuan University | Peng T.,China Bluestar Chengrand Chemical Co. | Wang F.-D.,China Bluestar Chengrand Chemical Co. | And 2 more authors.
Applied Surface Science

In order to investigate the effect of the polyamide benzimidazole group on the surface wettability and interfacial adhesion of fiber/matrix composites, surface features of two kinds of aramid fibers, poly (p-phenylene terephthalamide) fiber (Kevlar-49) and poly-(polyamide benzimidazole-co-p- phenylene terephthalamide) (DAFIII), have been analyzed by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and contact angle analysis (CAA) system, respectively. The results show that with the incorporation of the polyamide benzimidazole segment, more polar functional groups exist on DAFIII surface. The contact angles of water and diiodomethane on DAFIII surface get smaller. The surface free energy of DAFIII increases to 36.5 mJ/m2, which is 2.3% higher than that of Kevlar-49. In addition, DAFIII has a larger rough surface compared with that of Kevlar-49 due to different spinning processes. The interfacial shear strength (IFSS) of DAFIII/matrix composite is 25.7% higher than that of Kevlar-49/matrix composite, in agreement with the observed results from surface feature tests. SEM micrographs of failed micro-droplet specimens reveal a strong correlation between the fracture features and the observed test data. © 2011 Elsevier B.V. All rights reserved. Source

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