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2013, Volume 27 Issue 05 Publication date: 26 May 2013 Previous Issue Next Issue

China Plastics Industry(2012)

China Plastics Processing Industry Association

2013, 27 (05): 1-5 ; DOI: 10.19491/j.issn.1001-9278.2013.05.001

Abstract ( 1173 )

General situation of China plastics industry in 2012 was reviewed, including the output and export/import of plastics products, synthetic resins, and plastics processing machinery, as well as major economic data, such as the total industrial values, sales and profits of plastics products, etc. Analysis of the market of plastics products in 2012 was made, and the developing trend of China plastics industry in 2013 was proposed.

International Development Status of Seawater Reverse Osmosis Membrane Technology

2013, 27 (05): 6-11 ; DOI: 10.19491/j.issn.1001-9278.2013.05.002

Abstract ( 1409 )

The development of reverse osmosis (RO) membrane used for sea water desalination was reviewed, the membrane module and materials were also summarized. The traditional materials were based on inorganic, inorganic hybrid composite and organic materials, and the advanced materials included carbon nanotubes, molecular sieves, and graphenes. The international manufacturers of RO membrane were briefly introduced. A future prospect of sea water desalination was given.

Preparation and Developments of Nonmetal Superhydrophobic Materials

2013, 27 (05): 12-18 ; DOI: 10.19491/j.issn.1001-9278.2013.05.003

Abstract ( 1209 )

Principle and preparation methods of superhydrophobic materials were discussed in this paper. The preparation methods included etching, selfassembling, phase separation, template, chemical deposition, and solgel. The advantage, disadvantages, and application of these methods were discussed. Processed using laser radiation and plasma etching, perfect micronano structures could be obtained on nonmetal materials. Superhydrophobic surfaces could be obtained on low surface free energy polymers directly through laser etching and further modification was needless. Phase separation was appropriate for the preparation of superhydrophobic polymer film for it was simple, low cost, and suitable for large scale manufacture. Template method was simple and convenient to fabricate superhydrophobic materials.

New Research Progress in Modification of Unsaturated Polyester Resin

2013, 27 (05): 19-23 ; DOI: 10.19491/j.issn.1001-9278.2013.05.004

Abstract ( 1783 )

The advanced modification method of unsaturated polyester resin (UPR) was reviewed, including toughening, flame retarding, and lowering shrinkage. The formation of interpenetrating network and introduction of nano particle were also introduced. The existing problems and development prospects of UPR modification were discussed.

Influence of Chemical Microcrosslinking Modification on Polyurethane Performance

Xuejia DING

2013, 27 (05): 24-27 ; DOI: 10.19491/j.issn.1001-9278.2013.05.005

Abstract ( 1435 )

Into polyether polyurethane, different crosslinking agents were introduced, microcrosslinked polyurethane with a crosslinking degree between 0.4 %~7.0 % was prepared via double screws extrusion. With increasing crosslinking degree, the impact strength of the microcrosslinked polyurethane increased, tensile strength decreased, and the elongation at break was not affected. DSC analysis showed that the crosslinking decreased the crystallinity, melting point, and melting enthalpy of polyurethane.

Effect of Different Natural Pigments on Properties of PBS

2013, 27 (05): 28-33 ; DOI: 10.19491/j.issn.1001-9278.2013.05.006

Abstract ( 1237 )

Different pigments from punica granatum，rheum palmatum and scutellaria baicalensis were extracted and blended with poly (butylene succinate) (PBS). The crystalline state and thermal stability of the three blends were compared, and the influence of addition of pigments on the mechanical and antimicrobial properties of PBS were studied. It showed that the pigments had little effect on the crystalline behavior but the crystal size decreased and the crystallinity increased. The thermal stability of the blends was promoted when a small amount of pigments was added and the pigments had little effect on the mechanical properties; the blends all had good antibacterial properties.

Preparation and Characterization of Phenolic Foam Modified by Graphene Oxide

Shen Zhiwei

2013, 27 (05): 34-38 ; DOI: 10.19491/j.issn.1001-9278.2013.05.007

Abstract ( 1410 )

Graphene oxide modified phenolic resin was synthesized via insitu polymerization, using which phenolic foam was prepared. The mechanical property, thermal stability, and microstructure of the foam were characterized using FTIR, universal testing machine, TGA, and SEM. It showed that the cell size of phenolic foam loaded with 1.0 % graphene oxide was more uniform than unmodified phenolic foam, the compressive strength was increased by 65.0 % compared with unmodified phenolic foam, the surface powdering rate of phenolic foam modified by graphene oxide was significantly lower, graphene oxide had a significant improvement on the strength, toughness and thermal stability of the phenolic foam.

Degradation and Crystallization Behavior of Poly(ethylene terephthalate) Under Different Meltmixing Conditions

2013, 27 (05): 39-43 ; DOI: 10.19491/j.issn.1001-9278.2013.05.008

Abstract ( 1326 )

The degradation and crystallization behavior of poly(ethylene terephthalate) under different meltmixing conditions were investigated. PET chips were degraded to various degrees at different pretreatment conditions. The degradation rate was closely related to the water content; degradation not only led to an improvement of crystallization rate, but also resulted in a thickening of crystal lamella and increase of crystallinity. The crystallization peak temperature (Tcp), initial temperature (Tonset), end temperature (Tendset), and intrinsic viscosity showed good correlations. When intrinsic viscosity decreased, those temperature and crystallization rate increased.

Study on Preparation of Polyaniline/Multiwalled Carbon Nanotube Composites and Its Electrical Properties

2013, 27 (05): 44-48 ; DOI: 10.19491/j.issn.1001-9278.2013.05.009

Abstract ( 1298 )

Multiwalled carbon nanotubes (MWCNTs) were surface treated with an acid mixed, in which aniline was insitu polymerized forming conductive compositeswith ammonium persulfate as an oxidant. The morphology and performance of the composites were characterized using transmission electron microscope, Fourier transform infrared spectroscopy, UVvisible spectrophotometer, and Xray diffraction. The electrical properties of the composites were measured using twoprobe method and analyzed with mean field theory and a percolation threshold value of 2.36 % was observed. The diameter of the MWCNTs was 60~100 nm, and the length was about a few tens of micron. On the surface of MWCNTs a large number of —OH and —COOH groups were formed.

Isothermal Crystallization and Thermal Decomposition of Polyoxymethylene/Reactable Nanosilica Composites

2013, 27 (05): 49-55 ; DOI: 10.19491/j.issn.1001-9278.2013.05.010

Abstract ( 1268 )

Polyoxymethylene/reactable nanosilica composites were prepared via melt blending. The isothermal crystallization behavior of POM and its composites were studied with differential scanning calorimetry， and the effect of nanosilica was explored. The thermal decomposition was studied using thermogravimetric analysis. Avrami equation and HoffmanLaurititzen theory were used to analyze kinetics of isothermal crystallization of POM and its compositions. It showed that the reactable nanosilica (RNS) had a function of heterogeneous nucleation on the POM matrix, which enhanced the crystallization rate of POM, reduced the halftime for crystallization and the surface free energy of the developing crystals. The Avrami exponent n decreased, which indicated that RNS changed the crystallization and growth mechanism of POM. RNS improved the thermal stability and the onset temperate was improved 32 ℃ by 5 % RNS consents. The apparent activation energy of POM/RNS calculated using FOW and Friedman methods was higher than that of POM, which indicated that there must be some strong interaction between RNS and POM. RNS is both a nucleating agent and thermal stability agent of POM.

Study on TLCP/PF/GO Hybrid Composites

2013, 27 (05): 56-59 ; DOI: 10.19491/j.issn.1001-9278.2013.05.011

Abstract ( 1193 )

Composites of a thermotropic liquid crystal polymer (TLCP), phenol formaldehyde (PF), and silane coupling agent KH550 or KH560 treated graphene oxide were prepared via melting extrusion. The mechanical properties and friction and wear properties of the composites were studied. The abrasion surface of the composites was observed using scanning electron microscope. When graphene oxide was treated with KH560, the volume wear rate of the composites decreased by 20.6 % and 23.1 % at 150 ℃ and 250 ℃, respectively, the impact strength was increased by 18.6 %.

Research on Aging and Antiaging of Drip Irrigation Tapes

mamatjan yimit shuxin di Sanawar ABLA

2013, 27 (05): 60-64 ; DOI: 10.19491/j.issn.1001-9278.2013.05.012

Abstract ( 1521 )

UVA-340 lamp was used as an artificial acceleratedphotoaging source. The variation in carbonyl index, tensile strength, and elongation at break before and after aging was investigated, and the effect of antiaging agents on antiaging properties of drip irrigation tape was analyzed. It showed that the drip irrigation tapes with selfmade antiaging masterbatch had the best antiaging performance, compared with the 0 days aging sample, retention rate of elongation at break of the samples artificial aging for 10 days, 12 days and naturally exposed to 120 days aging were 94.3 %, 84.0 %, 61.9 %, respectively. UV340nm light at the condition of the radiation strength of 0.68 W/m2, blackboard temperature of 60 ℃, condensing temperature of 50 ℃, exposure time of 3 h, condensing time of 3 h, wind of 10 min, the aging rate was about ten times based on artificial accelerated photoaging more than that at natural environment.

Effect of Black Masterbatches on Tensile Strength of Weld Line of Flame Retardant Polypropylene

Yang Fan-Wen

2013, 27 (05): 65-68 ; DOI: 10.19491/j.issn.1001-9278.2013.05.013

Abstract ( 1270 )

The effect of composition of black masterbatches on tensile strength of weld line of halogeflame retardant polypropylene was studied. When added as an individual component, the carrier, dispersant, and carbon black had small effect on the tensile strength of weld line, and was not the primary reason for the screw column burst. However, in the black masterbatches, the high viscosity caused by increasing carbon black content and decreasing particle size resulted in low tensile strength of weld line and higher possibility of screws column burst. When PP was used as a carrier, the low resultant low viscosity may improve the tensile strength of weld line and lower the possibility of screw column burst.

Effect of Various Nanoparticles on Friction and Wear Properties of EP/GF Composites

2013, 27 (05): 69-72 ; DOI: 10.19491/j.issn.1001-9278.2013.05.014

Abstract ( 1183 )

Nano-Al2O3, nano-TiO2, nano-SiO2, and carbon nanotubes (CNTs) were separately introduced into glass fiber (GF) reinforced epoxy (EP) composites (GF 30 vt %). The friction and wear behavior of the composites under dry condition were evaluated with blockonring friction and wear tester. It showed that 1.0 wt % CNTs could significantly decrease the friction coefficient and specific wear rate of composites, while nano-SiO2, nano-Al2O3, and nano-TiO2 (all at a loading of 1.0 wt %) could slightly decrease specific wear rate of the composites.

Investigation of Tensile Property of ABS Resin and Its Toughening Mechanism

2013, 27 (05): 73-76 ; DOI: 10.19491/j.issn.1001-9278.2013.05.015

Abstract ( 1392 )

The effect of test temperature, tensile rate and aging time on the tensile properties and deformation mechanism of acrylonitrilebutadienestyrene (ABS) resin was investigated by tensile test and transmission electron microscope (TEM). The results showed that the yield stress decreased with the increase of the test temperature. The elongation at break of ABS resin was difficult to improve below the glass transition temperature of the high temperature zone，which was closely related to the property of its SAN matrix. The elongation at break decreased with the increase of the tensile rate. The crazing could be observed in all the samples obtained at different tensile rates, and the number of crazing increased with tensile rate. Furthermore, the propagation of crazing could be suppressed effectively in the sample under high tensile rate. The elongation at break of ABS resin significantly decreased after physical aging. The number of crazing increased with increasing physical aging time, and the cavity rubber particles arranged in a line could be observed.

Synthesis of Hyperbranched Aromatic Amine Triazine Polymer and Its Flame Retardation Performance on Polypropylene

2013, 27 (05): 77-81 ; DOI: 10.19491/j.issn.1001-9278.2013.05.016

Abstract ( 1255 )

A new hyperbranched aromatic amine triazine polymer was designed and synthesed by taking cyanuric chloride and Pphenylenediamine as raw material in acetone solvent, and its structure was confirmed by infrared spectroscopy. The intumescent flame retardant(IFR) which was composed of ammonium polyphosphate(APP) and the prepared hyperbranched polymer was used for the preparation of expansion flame retardant polypropylene (PP). Results showed that the target product was capable of excellent flame retardant and its carbon residue amount at 600 ℃ in N2 atmosphere was 44.8 %. The limiting oxygen index of PP was enhanced to 27.0 % from 17.5 % after proper addition of IFR, the heat release time was delayed by 625 s, and the peak of heat release rate was decreased by 85.7 %.

Effect of a New Type Nucleating Agent on Crystallization Behavior of PP

2013, 27 (05): 82-86 ; DOI: 10.19491/j.issn.1001-9278.2013.05.017

Abstract ( 1230 )

A new nucleating agent (NA) was applied to homopolypropylene (T30S) and copolymerizedpolypropylene (EPC30R), and the systems were characterized using differential scanning calorimetry，scanning electron microscopy，polarizing microscope，and Xray diffraction．The effect of NA on crystallization behavior and mechanical properties of PP was investigated．It showed that NA could not only enhance the crystallinity and crystallization peak temperature，decrease the spherulite size dramatically, and increase the crystallization rate，but also change crystal structure of PP．The notch impact strengths of T30S and EPC30R containing 0.3 % of NA were about 95 % and 43 % higher than their neat ones．

Effects of high shear and subcritical water on the devulcanization of SBR-based ground tire rubber and the mechanical properties of dynamic vulcanized HDPE thermoplastic elastomer

SHEN Wei-Wei

2013, 27 (05): 87-94 ; DOI: 10.19491/j.issn.1001-9278.2013.05.018

Abstract ( 1268 )

The effect of the screw rotation speed, temperature and pressure of subcritical water, and other additives on the devulcanization in the blends of the SBRbased ground tire rubber (GTR) with PEHD was studied. It showed that the high shear stress imposed by the twinscrew extruder and the subcritical water may promote the devulcanization. The faster the screw rotation speed or the higher the subcritical water temperature and pressure, the stronger the decomposition or degradation reaction. Nbutyl amine may significantly promote the devucanization and at the same time protected the double bond in the blend. When the screw rotation speed was 1000 r/min, the temperature and pressure of subcritical water were 220 ℃ and 2.4 MPa, respectively, a thermoplastic elastomer of DGTR/PEHD containing EPDM and with nbutyl amine provided a tensile strength of 12.8 MPa and an elongation at break of 614.6 %.

Influence of Screw Parameters of Metering Section on the PC Melting Temperature Homogeneity in the Injection Molding of Light Guide Plates

2013, 27 (05): 95-99 ; DOI: 10.19491/j.issn.1001-9278.2013.05.019

Abstract ( 1545 )

A 3-D nonisothermal flow field was simulated using CFD package Polyflow. The influence of different parameters of metering section on the temperature of PC melt in the injection screw was analyzed. It showed that the descending order of the influence of parameters on axial melt temperature difference was flight clearance, the angle of the inclined plane, screw channel depth, the lead of the screw, and the width of the screw flight; while the descending order of the influence on radical melt temperature difference was screw channel depth, the angle of the inclined plane, flight clearance, the lead of the screw, and the width of the screw flight.

Design of Injection Moulds with Ejection Mechanism Set in Slider Block

2013, 27 (05): 100-103 ; DOI: 10.19491/j.issn.1001-9278.2013.05.020

Abstract ( 1208 )

In order to prevent the molded part from sticking to the slider block, an ejection mechanism was set in the slider block. Taking the molded part of feeding bottle handle as an example, an injection mould was designed according to the analysis of the structure characteristics and processing technology of this part. The mould structure and its working process were introduced. The ejection mechanism set in half slider blocks, the forced demoulding mechanism and the cooling system were illustrated in detail. It was proved that the ejection mechanism set in slider was adequate for demoulding and was helpful to the quality of molded parts.

Design of an Electrohydraulic Control System in Blow Molding Machines Based on LabVIEW Software

Du Qiaolian

2013, 27 (05): 104-107 ; DOI: 10.19491/j.issn.1001-9278.2013.05.021

Abstract ( 1200 )

In the production of hollow products, in order to ensure uniform wall and save material, an electrohydraulic control system was designed for blow molding machines based on the LabVIEW software, with a high performance electrohydraulic proportional valve as the core of control system. The system relied on high speed operation and precision control, and closed cycle control of wall thickness was achieved. Test of the system showed that it had high accuracy and antiinterference, thus ensured smooth operation of large hollow products.