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The Toughening Behavior of the pp/POE Alternating Multilayered Blends under EWF and Impact Tensile Methods

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Chinese Journal of Polymer Science 2015年第10期33卷 1477-1490页

作者： Chun-hai Li Jian-feng Wang Ji-wei Guo 吴宏郭少云 The State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan University

The multilayered polypropylene （pp） and poly（ethylene-co-octene）（POE） sheets were prepared by the microlayered co-extrusion system. The essential work of fracture （EWF） and the impact tensile methods have been successfully used to evaluate the toughening behaviors of the pp/POE multilayered blends under quasi-static and dynamic uniaxial tensile stress, respectively. The experimental results indicate that the multilayered structure plays a key role in the toughening behaviors. On increasing the layer number of the multilayered blends, the specific essential work of fracture, we, increases obviously. As for the flwp, there is no obvious variation in the multilayered blends with low POE content （6.79%）, however, obvious enhancement is observed with increasing the layer number of the high POE content multilayered blends （16.57%）. Compared with the conventional blends, the multilayered blends with 6.79% POE content are effective to increase the value of we. Additionally, the multilayered blends with high layer numbers present absolute advantage in improving the impact tensile values.

关键词： Multilayer EWF Impact tensile pp POE

STUDY ON THE MISCIBILITY OF DYNAMICALLY VULCANIZED EPDM/pp BLEND BY POSITRON ANNIHILATION SPECTROSCOPY

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Chinese Journal of Polymer Science 2000年第2期18卷 123-128页

作者： Tao Jiang Xue-liang Jiang Shi-yuan Cheng Yi-qun Dai Shao-jie Wang Bo Wang Faculty of Chemistry & Material, Hubei University, Wuhan 430062, China Department of Physics, Wuhan University, Wuhan 430072, China Hubei Univ Fac Chem & Mat Wuhan 430062 Peoples R China Wuhan Univ Dept Phys Wuhan 430072 Peoples R China

Positron annihilation spectroscopy (PAS) was utilized to investigate the relationship between the free-volume hole properties and miscibility of dynamically vulcanized EPDM/pp blend. The results showed that the noncrystalline region of pp and EPDM in the blend was partially miscible and the miscibility of the blend became worse when the weight percent of EPDM was <50%. This was also demonstrated by DMTA and mechanical properties of the blends with various compositions.

关键词： EPDM pp dynamic vulcanization miscibility PAS

Preparation of amidoxime-based PE/pp fibers for extraction of uranium from aqueous solution

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Nuclear Science and Techniques 2019年第2期30卷 39-51页

作者： Xiao Xu Xiao-Jun Ding Jun-Xuan Ao Rong Li Zhe Xing Xi-Yan Liu Xiao-Jing Guo Guo-Zhong Wu Hong-Juan Ma Xiao-Yan Zhao School of Petrochemical Engineering Changzhou University Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

A novel amidoxime-based fibrous adsorbent,denoted as PE/pp-g-(PAAc-co-PAO), was prepared by preirradiation grafting of acrylic acid and acrylonitrile onto polyethylene-coated polypropylene skin-core(PE/pp)fibers using 60 Co γ-ray irradiation, followed by amidoximation. The original and modified PE/pp fibers were characterized by a series of characterization methods to demonstrate the attachment of amidoxime groups onto the PE/pp fibers. Breaking strength tests confirmed that the fibrous adsorbent could maintain good mechanical properties. The adsorption capacity of the PE/pp-g-(PAAc-coPAO) fibers was investigated in simulated seawater with an initial uranium concentration of 330 μg/L. The uranium adsorption capacity was 2.27 mg/g-adsorbent after 24 h in simulated seawater, and the equilibrium data were well described by the Freundlich isotherm model. The PE/pp-g-(PAAc-co-PAO) adsorbent exhibited good regeneration and recyclability during five adsorption-desorption *** adsorption test was also performed in simulated radioactive effluents with uranium concentrations of 10 and100 μg/L. The effect of the pH value on the adsorption capacity was also studied. At a very low initial concentration 10 μg/L solution, the PE/pp-g-(PAAc-co-PAO)fiber could remove as much as 93.0% of the uranium, and up to 71.2% of the uranium in the simulated radioactive effluent. These results indicated that the PE/pp-g-(PAAcco-PAO) adsorbent could be used in radioactive effluents over a wide range of pH values. Therefore, the PE/pp-g-(PAAc-co-PAO) fibers, with their high uranium selectivity,good regeneration and recyclability,good mechanical properties, and low cost, are promising adsorbents for extracting uranium from aqueous solutions.

关键词： Amidoxime groups Pre-irradiation PEcoated pp skin-core fiber Adsorption Uranium

Analysis on Interface Characteristics of FeNi_p/pp Nanocomposites

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Journal of Wuhan University of Technology(Materials Science) 2019年第6期34卷 1248-1253页

作者： ZHONG Qi ZHU Zhenghou BAI Ruru CHEN Jie College of Material Science and Engineering Nanchang UniversityNanchang 330031China

The FeNip/pp nanocomposites were successfully prepared by the two-step blending method and the permeable layer interface with thickness of 2 to 10 nm was formed on the surface of nanopowders. The interface is composed of the lattice and molecular chain, in which the polypropylene molecular chain enters the lattice defects and forms a cross-linked structure. The interface causes the FeNi nanopowders to be well compatible with the polypropylene matrix and uniformly dispersed in the matrix, and significantly improves the mechanical properties of composites. The tensile strength of 2 wt% FeNip/pp composites reached 38 MPa, 23% higher than that of pure pp resin. The shielding performance of 20 wt% FeNip/pp composites reached 9.8 dB in the frequency range of 1-100 MHz.

关键词： pp nanocomposites interfacial structure mechanical properties shielding properties

Study of the structure and the mechanical properties of dynamically cured pp/MAH-g-SEBS/epoxy blends

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Chinese Chemical Letters 2009年第7期20卷 877-880页

作者： Xue Liang Jiang Yin Xi Zhang School of Materials Science and Engineering Wuhan Institute of Technology Wuhan 430073 China Research Institute of Polymer Materials S-hanghai Jiaotong University Shanghai 200030 China

A new method concerning with the simultaneous reinforcing and toughening of polypropylene （pp） was reported. Dynamical cure of the epoxy resin was successfully applied in the pp/maleic anhydride-grafted styrene-ethylene-butylene-styrene （SEBS） triblock copolymer, and the obtained blends named as dynamically cured pp/MAH-g-SEBS/epoxy blends. The stiffness and toughness of the blends are in a good balance, and MAH-g-SEBS was acted as not only an impact modifier but also a compatibilizer. The structure of the dynamically cured pp/MAH-g-SEBS/epoxy blends is the embedding of the epoxy particles by the MAH-g- SEBS.C2009 Xue Liang Jiang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Dynamical cure Epoxy resin pp MAH-g-SEBS

INVESTIGATION OF pp-EPR DIBLOCK COPOLYMER AS COMPATIBILIZER FOR pp/EPT BLEND

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Chinese Journal of Polymer Science 1985年第3期3卷 216-225页

作者：冯之榴董丽松张伯兰方正杨永宽 E.T.L Voong and Voong Tse Lieu Changchun Institute of Applied Chemistry Academia Sinica Changchun

Blending isotactic polypropylene (pp) with ethylene-propylene terpolymer (EPT) is one of thesimplest and most effective ways for toughening pp. In order to further improve the toughness ofpp/EPT blend and to enhance the stability of the dispersed rubber phase, a diblock copolymer com-posed of pp and ethylene-propylene rubber blocks (pp-EPR) was added into the blend, as it is con-sidered that 'forced compatibility' of the two components will be effected through the two chemi-cally bonded blocks, while two-phase structure still remains. Experimental results indicate that pp-EPR is an effective compatibilizer for pp/EPT blend. Itnot only increases the toughness of the blend, but also decreases the loss of tensile strengths usuallyaccompanying the toughening of plastics with an elastomer, which is very well explained by the mor-phological structure changes when an appropriate amount of pp-EPR was added into the blend.

关键词： EPT INVESTIGATION OF pp-EPR DIBLOCK COPOLYMER AS COMPATIBILIZER FOR pp/EPT BLEND pp EPR AS

Effects of Porosity on Structure and Performance of pp Meshes for Reparing Pelvic Floor Defects

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Journal of Donghua University(English Edition) 2014年第5期31卷 704-708页

作者：鲁瑶陈艳春张佩华 Key Laboratory of Textile Science and Technology Ministry of EducationDonghua University

Currently,polypropylene( pp) synthetic mesh is a kind of common material used for pelvic floor's repairing and *** repairing mesh is generally made with different hole shape and *** is one of the most important indicators of pp *** different-structure pp meshes are selected through adopting corresponding target density in the heat setting process for meshes owning different *** performance and structure of two kinds meshes with different porosity are *** results showed that: the increase of porosity leaded to the decreases of meshes' thickness,tensile strength and bursting ***' bending stiffness was reduced and they became softer,but there was no significant change in suture pulling-out force, which maybe associated with the large aperture of pp meshes.

关键词： polypropylene ( pp ) pelvic mesh porosity tensilestrength bursting strength suture pulling-out force

MORPHOLOGY OF VULCANIZED EPDM/pp BLEND THERMOPLASTIC ELASTOMERS

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Science China Chemistry 1986年第12期29卷 1233-1238页

作者：殷敬华周恩乐金桂萍纪锋黄葆同 Jiamusi Institute of Chemieal Engineering Changchun Institute of Applied Chemistry Academia Sinica

Dynamic vulcanization of rubber in rubber/plastic blend thermoplastic elastomers poses challenge to the traditional concept on morphology of thermoplastic elastomers. TEM and SEM micrographs of OsO-stained samples and samples with EPDM dissolved by heptane or etched with CrO/HSOreveal that the blends with uncrosslinked EPDM have a predominant component as the continuous phase, while the blends with crosslinked EPDM always have pp as the continuous phase even at R/P>50/50. In the latter case, crosslinked EPDM exists as the micro-domains imbedded in the pp matrix. This explains the plasticity and higher strength of the crosslinked blends.

关键词： EPDM pp MORPHOLOGY OF VULCANIZED EPDM/pp BLEND THERMOPLASTIC ELASTOMERS

Separating PH from pp by Relativization

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Acta Mathematica Sinica,English Series 1992年第3期8卷 329-336页

作者：付斌 Computer Science Department Beijing Computer Institute

We construct an oracle A such that ∑~Г■ppA. So the polynomial timehierarchy is separated from the polynomial time probabilistic complexity class in relativization.

关键词： pp length