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2011, Volume 25 Issue 03 Publication date: 26 March 2011 Previous Issue Next Issue

Review of China Modified Plastics Industry During the Eleventh Five-year Plan and Its Prospect During the Twelfth Five-year Plan

Yingjun LIU

2011, 25 (03): 1-6 ; DOI: 10.19491/j.issn.1001-9278.2011.03.001

Abstract ( 1873 )

The development of modified plastics industry during the eleventh five-year plan period was introduced.Modified plastics industry has developed into a uprising industry including about 1000 enterprises being engaged in modified plastics；200 related enterprises being engaged in auxiliaries，additives，compounding machinery and processing equipment；and more than one hundred thousand people in employment. Some new type modified plastics including ACS，PA/ABS alloy，high barrier nano-composite poly（ethylene terephthalate）（PET） for bottles and films，new anti-static filler， new talc masterbatch，environmentally friendly modified plastics，carbon fiber reinforced plastics，and other new types of modified plastics products were developed. Finally，the trends and the main tasks of modified plastics during the twelfth five-year plan period were introduced.

Research Development of Thermally Conductive Polymer Composites

KONG Jiao-Yue

2011, 25 (03): 7-12 ; DOI: 10.19491/j.issn.1001-9278.2011.03.002

Abstract ( 2436 )

Based on the general thermal conducting principle of metal，inorganic nonmetallic materials，and polymer materials，two kinds of thermal conducting mechanisms of polymer/heat conductive filler composites were introduced，i.e.，thermal nets chain mechanism and thermalelastic combination mechanism. These mechanisms could explain various phenomena of heat conduction in polymer composites. Some thermal conduction models suitable for fiber and grain filled polymeric composites were presented. Effect of resin，heat conductive filler，and temperature on the thermal conductivity of polymer composites was discussed.

Research Progress in Flame Retardant Plastics/Wood Composites

2011, 25 (03): 13-17 ; DOI: 10.19491/j.issn.1001-9278.2011.03.004

Abstract ( 2469 )

The recent progress in the research of halogen-free flame retardant for biomass fiber- polymer composites was reviewed. Firstly，combustion properties of the composites were analyzed，then the effects of halogen-free retardants such as aluminum-magnesium，intumescent， phosphorus-containing，and nanoparticles flame retardants on the flame retardancy and mechanica properties were summarized. Based on the current problems in the flame-retardant composites，its development trend was prospected.

Progress in CTBN toughening modification of thermosetting resins

LIU Nai-liang

2011, 25 (03): 18-24 ; DOI: 10.19491/j.issn.1001-9278.2011.03.005

Abstract ( 2678 )

The mechanism and research progress in the toughening of thermosetting resins(including epoxy, phenolic, cyanate ester, and bismaleimide resins) using liquid carboxyl terminated butadiene nitrie rubber (CTBN) were reviewed. The present problems under study were pointed out and the study direction of CTBN toughening of thermosetting resins was suggested.

Microphase Separation Structure and Analysis of Phase Transition Theory of Polyurethane Phase Change Materials

GAO Yi

2011, 25 (03): 25-28 ; DOI: 10.19491/j.issn.1001-9278.2011.03.006

Abstract ( 2355 )

Using polyethylene glycol (PEG) as soft segments，1，4-butanediol(BDO)as chain extender, and modified MDI as curing agent，a series of polyurethane phase change materials (PUPCM) was obtained. The change in morphology and properties of PUPCM during heating-cooling cycles was online observed using polarization microscope(POM)，differential scanning caborimetry(DSC)，and other testing methods. Atomic force microscope(AFM) revealed that the nature of phase change during the thermal cycling was the crystalline-amorphous transition and the resulted microphase separation，which influenced the thermodynamic and crystallization properties.

Effect of PBA-g-SAN on Properties and Structure of ASA Resin

2011, 25 (03): 29-33 ; DOI: 10.19491/j.issn.1001-9278.2011.03.007

Abstract ( 2219 )

PBA latex was synthesized by emulsion polymerization，onto which acrylonitrile and styrene monomers were grafted. The grafted product was melt blended with SAN copolymer forming an ASA resin. The effect of grafting monomers and PBA latex size on the structure and property of ASA resin was studied. It showed that the grafting degree was increased with increasing loading of grafting monomers，and the impact strength of ASA resin increased and then decreased with an increasing grafting monomers and PBA latex particle size. When the grafting monomers content was 3 wt % of BA monomer，ASA resin reached the maximum impact strength of 110 J/m. Dynamic mechanical thermal analysis (DMTA) showed that the Tg of the grafted PBA increased with increasing grafting monomers，decreased and then increased with increasing PBA latex size. Scanning electron microscope revealed that the PBA latex uniformly dispersed in SAN matrix with a few of particles coagulated.

Study on the Thermal Stability of CPVC

2011, 25 (03): 34-38 ; DOI: 10.19491/j.issn.1001-9278.2011.03.008

Abstract ( 2233 )

The effect of primary heat stabilizer，auxiliary heat stabilizer, inner lubricant，and external lubricant on the processability，thermostability and mechanical properties of chlorinated Poly（vinyl chloride）（CPVC）was studied. It showed that the processability and the thermostability were best when the primary stabilizer was 3.0 phr，auxiliary heat stabilizers Pb-St and Ba-St were 0.7~1.1 phr each, inner lubricant H-St was 0.5 phr, external lubricant petrolin was 0. 6 phr. The impact strength，tensile strength，and Vicat softening point were 20. 19 kJ/m2， 67. 36 MPa，122. 3℃，respectively.

Preparation and Properties of P(BA-AA)/Nano-OMMT Composites

Liu Ling zhao-zhong xing peng yan gui-nan xiao

2011, 25 (03): 39-42 ; DOI: 10.19491/j.issn.1001-9278.2011.03.009

Abstract ( 1908 )

Emulsion polymerization was adopted in the preparation of P（BA-AA）/organically modified nano montmorillonite (nano-OMMT) composite. X-ray diffraction (XRD) and fourier transform infrared spectrometry (FTIR) were used to characterize the structures of the composites. The thermal stability was examined by thermogravimetric analysis (TGA)，and mechanical properties of the composites were also tested. When monomer ratio BA-AA was 3：2，partially intercalated and partially exfoliated nanocomposite was obtained. Adding 3%~7% nano-OMMT can significantly improve thermal stability of the composites. When the nano-OMMT mass fraction was 7%，its thermal stability was the highest. The addition of nano-OMMT effectively improved the tensile strength of the composites.

Study of Cellulose Acetate Plasticized with Tributyl Citrate and Glyceryl Triacetate

Quanping ZHANG

2011, 25 (03): 43-48 ; DOI: 10.19491/j.issn.1001-9278.2011.03.010

Abstract ( 2603 )

Effect of plasticizers，tributyl citrate (TBC) and glyceryl triacetate(GT)，on the mechanical and rheological properties of cellulose acetate (CA) was investigated. It showed that the plasticizing efficiency of GT was better than that of TBC for the same addition level. When the content of TBC or GT was 25%，the melt flow rates were 0. 060 g/（10 min）for TBC and 5. 42 g/（10 min）for GT. The system containing 5% GT and 20% TBC gave rise to an impact strength of 9. 2 kJ/m2 and a melt flow rate of 3. 63 g/（10 min）.

The research about the heating procedure of Extruded polystyrene

WANG Zhao-Jun

2011, 25 (03): 49-51 ; DOI: 10.19491/j.issn.1001-9278.2011.03.011

Abstract ( 2336 )

The thermolabile characteristics of extruded polystyrene (XPS) with different heating methods were studied by the heating rate of 10K/min, as well as the release of the gas during the heating procedure .The sample was tested by Thermogravimetry- Infrared (TG- FTIR). The expansion and contraction of the sample with the heating procedure was carried out in Sintering Image Instrument (SII) to determine the temperature of melting and flow; The flow temperature of 212℃.

Indentation Size Effect of Viscoelastic Polymers by Dynamic Nanoindentation

2011, 25 (03): 52-56 ; DOI: 10.19491/j.issn.1001-9278.2011.03.013

Abstract ( 1990 )

Flexibility factor analysis was proposed for exploring the indentation size effect (ISE) of viscoelastic polymers，and the influencing factors of ISE were analyzed by dynamic nanoindentation for PMMA and thermoplastic polyurethane (TPU).It was found that the carrier load was the key factor of ISE of linear viscoelastic materials in dynamic nanoindentation using Berkovich tip，and the harmonic load control methods have little influence on ISE. The viscoelastic performances by dynamic nanoindentation agree with the dynamic mechanical analysis(DMA)results as the carrier displacement was larger than the critical value.

Effect of Mixture Techniques on the Properties of PP/Nano-Si0₂ Composites

DONG Jinhu

2011, 25 (03): 57-60 ; DOI: 10.19491/j.issn.1001-9278.2011.03.014

Abstract ( 2084 )

Solution, melt, and double-phase mixing technique were used to prepare PP/nano-SiO2 composites. The effect of mixing methodology and content of nano-SiO2 on the mechanical properties and microstructure of PP/nano-SiO2 composites was studied. It showed that the dispersion efficiency of nano-SiO2 was in the order of solution, double-phase, and melt mixing. When the content of nano-SiO2 exceed 3%，the composite based on double-phase mixing formed diphase structure. When the content of nano-SiO2 exceeded 5%，all three methods produced layered structure, which was not good for mechanical properties. Therefore, the content of nano-SiO2 of 3%，and double-phase mixing were preferred, which caused the tensile strength increased by 21. 3%，the elongation at break increased by 27.6%，and the impact strength increased by 131. 1%.

Simulation of Injection Molding of Micro Fluidic Chips

2011, 25 (03): 61-64 ; DOI: 10.19491/j.issn.1001-9278.2011.03.015

Abstract ( 2087 )

The micro fluitlic chips were studied in this work. The configuration of the micro fluitlic chips were designed by software Moldflow，which was used to simulate the micro fluitlic chips under different process parameters. It showed that the melt temperature had little effect on the filling time，while filling rime decreases with increasing injection speed. Injection pressure decreases with increasing melt temperature and injection speed. The warpage of the fluitlic chip can be reduced by increasing the melt temperature and injection speed.

Experimental Study on Flexural Behavior of Pre-stressed Concrete Beams Reinforced with BFRP Tendons

FEI Wei

2011, 25 (03): 65-69 ; DOI: 10.19491/j.issn.1001-9278.2011.03.016

Abstract ( 2251 )

To investigate the flexural behavior of BFRP tendon reinforced concrete beams, one full pre-stressed concrete beam and two partially pre-stressed BFRP tendon reinforced concrete beams, and one BFRP bar reinforced concrete beam were tested. The cracking, yield, failure load，and the development of the deflection and the cracks were tested. It showed that the cracking resistance capacity of the beams was enhanced through using BFRP tendons, and the width of deflection and cracks were better controlled. The failure load of the beams was enhanced as the reinforcement ratio of steel bars increased，the failure loads of the full pre-stressed beam and the non pre-stressed beam were basically unchanged. By using steel bars, the width and the interval of cracks were decreased, and the ductility was improved. The distribution and quantity cracks in the full pre-stressed and the non pre-stressed beams were basically the same. The cracks in the partially pre-stressed concrete beams were much more than the full pre-stressed and the non pre-stressed beams.

Extrusion Foaming Behavior of Different High Density Polyethylene Foaming Systems

Bengang LIU Zhehan ZHAO Ludong HE Yunlong XUE WANG Xiangdong Zhongjie DU

2011, 25 (03): 70-74 ; DOI: 10.19491/j.issn.1001-9278.2011.03.017

Abstract ( 2275 )

Foamed samples of three kinds of PE-HD，including PE-HD 7600M，PE-HD 50005, and PE-HD 5200，and PE-HD/nano-montmorillonite composites were prepared via extrusion foaming. Lrystallization behavior of 7600M，5000S，and 5200B was studied by differential scanning calorimetry (DSC). Density and electron micrographs of the three grades of PE-HD and their nano-OMMT composite foam samples were tested via true density meter and scanning electron microscopy(SEM).The result showed that melt flow rate had effect on the extrusion foaming. The lowest density of the foamed samples was 0. 59 g/cm3 when the resin was 5200B and the content of foaming agent was 2 phr. The foaming effect was enhanced when the melt flow rate of the resin was higher. The addition of nano-montmorillonite improved the extrusion foaming of PE-HDs with higher melt flow rates.

Effect of Light Stabilizers and Antioxidants Low-density Polyethylene under on Structural Stability of Linear Xenon-arc Irradiation

WU Peng Nurulla ISMAYIL

2011, 25 (03): 75-79 ; DOI: 10.19491/j.issn.1001-9278.2011.03.018

Abstract ( 2269 )

Under irradiation of xenon-arc，effect of antioxidant 1010，168 or light stabilizer 622 on the photo-stability of linear low-density polyethylene(PE-LLD) was studied. The properties and structure of PE-LLD before and after irradiation were characterized through mechanical testing and gel permeation chromatography (GPC). It showed that the reserved elongation at break of PE-LLD was less than 50% after 3 days′ irradiation; the reserved elongation at break of PE-LLD was less than 50% after 7，6，and 15 days′ irradiation for systems containing 0. 15 phr of antioxidant 1010，168 or light stabilizer 622，respectively. When antioxidant 1010，168 and light stabilizer 622 were used together, obvious synergistic photooxidative aging resistance of PE-I,LD was observed.

Application of Water Mill Superfine-BaSO₄ in Polyolefin Color Masterbatch

LIN Guang-Qiang Yancong FENG Sanzhao WANG Hui QIAO Lifeng WU Haibin LI Hesong PENG Dongjun LV

2011, 25 (03): 80-84 ; DOI: 10.19491/j.issn.1001-9278.2011.03.019

Abstract ( 1885 )

The morphology and particle size distribution were investigated with SEM and particle size analyzer. The effect of superfin-BaSO4 on color properties of red，yellow，and blue polyolefin masterbatches was explored. It showed that when replaced pigment with 20% superfin-BaSO4 in the color masterbatch，the dispersion of pigments in the plastics was enhanced，with the best improvement observed in red pigment systems.

Research on Moulding Process of Waste Plastics and Carbide Slag Compound Formworks

2011, 25 (03): 85-88 ; DOI: 10.19491/j.issn.1001-9278.2011.03.020

Abstract ( 1720 )

Compound formworks were made from waste plastics (PE，PP) and carbide slag，and two molding methods，hotpressing and extrusion were compared. It showed that the extrusion molding was superior to hotpressing, dense and even-texture，better mechanical properties were obtained. The impact strength，the flexural strength，and the elasticity modules of the extrusion based formworks were 29. 8%，36. 6%，and 25. 9% higher than those based on hotpressing molding.

Research on Barrels of Precision Injection Molding Machine Temperature Control and Anti-interference Based on Fuzzy-PID

LIN Rong-Chuan

2011, 25 (03): 89-93 ; DOI: 10.19491/j.issn.1001-9278.2011.03.021

Abstract ( 2128 )

Optimizing time control and fuzzy PID control are integrated to control the temperature of barrels of injection machines in real time. By using fuzzy reasoning rules，fuzzy tables for PID parameters were obtained，and the parameters of PID algorithm can be modified on line by looking up these tables，and this method has ability to resist the time-varying of system parameters. This program was simulated by Matlab simulation and tested in experiment. It showed that the fuzzy PID controller had good performance in dynamic state and high accuracy in temperature control. The deviation of temperature was±1. 5 ℃，which can be specification for control requirements.

Mould Design of American Style PVC Windows Profile Section

XIAO Xue-Shi

2011, 25 (03): 94-96 ; DOI: 10.19491/j.issn.1001-9278.2011.03.022

Abstract ( 2135 )

This article discusses how to improve the design quality of PVC window profiles from the point view of assembling and molding process. Window profile sections of American style were taken as references. According to the analysis of the flow channel, an integrated study was carried out on the following aspects: the layout design of water and vacuum in the calibrator; the dimension matching require between the calibrator and hot die; the flow of PVC compounds and especially the cooling rules of interior web in the calibrator; and the function research of tank plate in the water tank.