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2016, Volume 30 Issue 02 Publication date: 26 February 2016 Previous Issue Next Issue

Research Progress in Modification of ABS/PC Blends for Automotives

2016, 30 (02): 1-5 ; DOI: 10.19491/j.issn.1001-9278.2016.02.001

Abstract ( 861 )

Modification of acrylonitrilebutadienestyrene copolymer/polycarbonate(ABS/PC) blends for automotives was reviewed. The modification endows ABS/PC blends with improved flame retardancy, conductivity, and mechanical properties. Some other modified materials used in automotives were also discussed. In the end, the research trend of the modification of ABS/PC blends and its application in automobiles was prospected.

Research Progress in Flame Retardant Polystyrene/Layer Inorganic Nanocomposites

2016, 30 (02): 6-10 ; DOI: 10.19491/j.issn.1001-9278.2016.02.002

Abstract ( 713 )

Flame retardant properties and thermal stability of polystyrene(PS)/montmorillonite(MMT) nanocomposites, PS/layered double hydroxides(LDH), and PS/graphene(GO) were summarized. By introducing additive and reactive flame retardant agents into PS, the flame retardant and thermal stability of the above three nanocomposites were greatly improved. At the end,research and application perspectives of flame retardant polystyrene/layer inorganic nanocomposites were prospected.

Surface Interaction of Selfassembly Functional Polymeric Materials

2016, 30 (02): 11-19 ; DOI: 10.19491/j.issn.1001-9278.2016.02.003

Abstract ( 875 )

The surface interaction of polymers and its influencing factors such as hydrogenbond interaction,van der Waals energy, electrostatic interaction, and dipoledipole force were analysed. The surface interaction of functional materials such as selfassembly nanomaterials, selfassembly block copolymers and selfassembly biological macromoleculars was introduced. In addition, the effects of selfassembly mechanism, the structure and performance were analyzed according to interaction types and interface strength. Furthermore, the development, application prospect and potential values of new functional polymeric materials were presented.

Preparation and Performance of Polybutylene Terephthalate/Grapheme Sheet Composites by Solution Mixing

2016, 30 (02): 20-23 ; DOI: 10.19491/j.issn.1001-9278.2016.02.004

Abstract ( 698 )

Abstract: The composites of grapheme sheet（GS）/ polybutylene terephthalate(PBT) and functional grapheme sheet(GS-KH550)/ polybutylene terephthalate(PBT) are fabricated by solution blending , the performance of PBT、GS/PBT、GS-KH550/PBT composites have been investigated. The results show that the melting temperature(Tm) and the crystallization temperature(Tc) of PBT increase slightly because of the addtion of grapheme sheet; GS and GS-KH550 promote crystallization of PBA and make it crystallizate perfectly , the crystallinity and crystal size increase but they don’t change the crystal type of PBT; The notched impact strength of functional grapheme sheet(GS-KH550)/ polybutylene terephthalate(PBT) composite obviously improve.

Molecular Chain Structure Analysis of a High Density PERT Ⅱ Pipe Resin

2016, 30 (02): 24-27 ; DOI: 10.19491/j.issn.1001-9278.2016.02.005

Abstract ( 521 )

The molecular and crystalline structures of Lyondell Basel Company’s high density heatresistant polyethylene pipe resin 4731B were analyzed by solvent gradient classification combined with gel permeation chromatography(GPC), carbon nuclear magnetic resonance(13C-NMR), differential scanning calorimeter (DSC). It was found that the crystallinity was 63 %, the chip thickness was 31 nm; the molecular weight distribution was bimodal, MWD was 18.0, MW of low molecular weight part was 4.0×103~3.0×104, that of high molecular weight part was 3.0×105~6.0×105. Short branched chains evenly distributed in the higher polymer chains, comonomer content is more than 1.25 %. Ratio of high and low molecular weight components was (50~55)∶(45~50).

Properties of POE/mPE/PE-HD Modified PE-LD Heat Sealing Films

2016, 30 (02): 28-31 ; DOI: 10.19491/j.issn.1001-9278.2016.02.006

Abstract ( 1073 )

Ethyleneoctene copolymer (thermoplastic elastomer POE) was used to improve the heat sealing temperature and tensile strength of the low density polyethylene(PE-LD). Metallocene polyethylene (mPE) was used to increase heat seal strength of PE-LD. High density polyethylene (PEHD) was used to increase tensile strength of PE-LD film. The transverse tensile strength, longitudinal tensile strength, and heat seal strength of the film increased 17.21、29.73 MPa, and 16.11 N/15 mm, respectively, while the outer layer of the film was PE-LD, and the middle layer was PE.LLD(7042)∶PE.HD=70∶30, and the inner layer was PE-LLD(7050)∶PE-LD∶ POE(9361)∶mPE(M4707EP)=10∶80∶5∶5.

Preparation and Properties of Conductive Polyaniline/Rubber Powders Blends

2016, 30 (02): 32-38 ; DOI: 10.19491/j.issn.1001-9278.2016.02.007

Abstract ( 527 )

Modified rubber powder was prepared by treating waste tire rubber powder with silane coupling agent (KH560). Polyaniline/ modified rubber powder conductive blends were prepared by insitu polymerization and using ammonium persulfate as initiator. The effect of the ratio of raw materials, the reaction temperature and time on the conductivity of the blends was studied by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), four-probe resistivity meter, and electrochemical workstation. It showed that the dispersion of rubber powders was significantly improved through modification. The conductivity of polyaniline/modified rubber powder conductive blends reached 4.79 S/cm under the conditions of the temperature of 10 ℃, the ratio of ammonium persulfate to aniline of 1∶1, the concentration of hydrochloric acid of 1.0 mol/L, and the reaction time of 10 h.

Surface Modification of PEEK by Immobilization of Ocarboxymethyl Chitosan for Improvement of Blood Compatibility

2016, 30 (02): 39-42 ; DOI: 10.19491/j.issn.1001-9278.2016.02.008

Abstract ( 864 )

Poly(ether ether ketone) was surface modified via immobilization of O-carboxymethyl chitosan. Acrylic acid was first introduced onto surface of PEEK by UV-initiated graft polymerization. Then O-carboxymethyl chitosan was subsequently covalent bonded onto the PEEK film. XPS, SEM, and water contact measurements were used to characterize the modified surface. The surface wettability was significantly improved with water contact angle drop from 86 ° for blank PEEK to 42 ° for modified PEEK. Palate adhesion experiments showed that the modified PEEK exhibit anti-coagulation properties.

Preparation and Properties of PEGDA Cross Linked PAA-K Waterabsorbency Resin

2016, 30 (02): 43-48 ; DOI: 10.19491/j.issn.1001-9278.2016.02.009

Abstract ( 830 )

Superabsorbent potassium polyacrylate(PAAK) polymer was synthesized via UV irradiation or microwave copolymerization of acrylic acid in the presence of an initiator (2, 2-dimethoxy-phenyl ethyl ketone or ammonium persulfate) and crosslinker (polyethylene glycol diacrylate). Properties of PAA-K was characterized by Fourier transform infrared spectroscopy(FTIR), thermogravimetry (TG), and energy dispersive spectrometer (EDS). It showed that under the optimized conditions,water absorption of PAA-K made by UV irradiation were 3297 g/g in distilled water and 419 g/g in 0.9 wt % NaCl solution. Those for microwave radiation were 2861 g/g in distilled water and 414 g/g in 0.9 wt % NaCl solution.

Preparation of Chlorinated Poly(vinyl chloride) Grafted with Maleic Anhydride and Its Application in Poly(vinyl chloride)

2016, 30 (02): 49-53 ; DOI: 10.19491/j.issn.1001-9278.2016.02.010

Abstract ( 651 )

Chlorinated poly(vinyl chloride) (CPVC) was grafted with maleic anhydride(MAH) via solid-phase grafting copolymerization.Grafting degree (GD) of copolymer CPVC-g-MAH was 2.91 %. The thermal stability, impact strength, and processability of the PVC/CPVC-g-MAH blends were evaluated, and compared with those of PVC/CPVC blend. It showed that CPVC-g-MAH exhibited a higher thermal stability than CPVC. The impact strength of PVC/CPVC-g-MAH blends was higher than that of PVC/CPVC blends. The equilibrium torque of PVC/CPVC-g-MAH blends was lower than that of PVC/CPVC blends, which indicated CPVC-g-MAH provided processing.

Study on Polybutylene Terephthalate Toughened by Ethylene-methyl Acrylate-glycidyl Methacrylate Terpolymer

2016, 30 (02): 54-58 ; DOI: 10.19491/j.issn.1001-9278.2016.02.011

Abstract ( 914 )

Toughened polybutylene terephthalate(PBT) was prepared by blending with self-made ethylene-methyl acrylate-glycidyl methacrylate terpolymer and a commercial toughening agent. Notched impact strength, elongation at break, and melt flow rate were tested. It showed that toughening effect was the best when the grafting degree of ethylene-methyl acrylate-glycidyl methacrylate terpolymer was 1.96 %, and its content in PBT was 15 %. The notched impact strength and the elongation at break of the toughened PBT increased by 65 % and 30.6 %, respectively.

Surface Modification of Nano-silica by Organic Phosphorus and Its Application in Polypropylene

2016, 30 (02): 59-63 ; DOI: 10.19491/j.issn.1001-9278.2016.02.012

Abstract ( 589 )

Nanosilica was surface modified with phosphorus oxychloride and isooctyl alcohol, and was introduced into polypropylene(PP) forming composites. The properties of the modified nanosilica and the composite were investigated by Fourier transform infrared spectrometer (FTIR), differential scanning calorimeter (DSC), and universal material machine. It was found that the surface of the modified silica had no hydroxyl groups, the grafting degree of organic phosphorus on silica was 16 %, its particle size was between 4 and 50 μm, and it had good hydrophobicity. It also showed that the section of the composite was regular, its melting point was basically the same as PP. The corresponding temperatures of the composite in various stages of weight loss were 7~10 ℃ higher than those of PP. The organic phosphorus modified silica could improve the thermal stability and flame retardant property of PP composite.

Effect of Nucleating Agent on Properties of Extruded Polystyrene Foam Boards

ZHANG Yongiia, LIU Bengang, WANG XiangdongWANG Yaqiao, CHEN Peng, WANG Wenbo

2016, 30 (02): 64-70; DOI: 10.19491/j.issn.1001-9278.2016.02.013

Abstract ( 95 )

Study on Relationship Between Product Quality and Cavity Pressure Curve

2016, 30 (02): 71-74 ; DOI: 10.19491/j.issn.1001-9278.2016.02.014

Abstract ( 857 )

The transform regulation of cavity pressure in each injection stage was studied through the cavity pressure data obtained from factorial experiments. The relationship between cavity pressure and product quality in different stages was analyzed. The results demonstrated that product quality had a strong relationship with cavity pressure. Both the increase of cavity pressure in mold filling stage and decline of cavity pressure in cooling stage had influence on product quality while the former being more important.

Experimental Study on Factors Affecting PMMA Melt Viscosity

2016, 30 (02): 75-78 ; DOI: 10.19491/j.issn.1001-9278.2016.02.015

Abstract ( 878 )

Experimental study was carried out on the melt viscosity of different types of PMMA. It showed that rheological behavior of three PMMA was different because their molecular was different, and under the same temperature and pressure, the higher the molecular weight, the larger the viscosity. With increasing extrusion pressure the shear rate increased, shear viscosity decreased, so the melt gave the characteristics of shear thinning. With increasing temperature, the shear viscosity decreased, and gradually become equal when the temperature reached 280 ℃.

Effect of Interaction of Structure Features on Warping Deformation of Injection Molded Plastic Gears

2016, 30 (02): 79-82 ; DOI: 10.19491/j.issn.1001-9278.2016.02.016

Abstract ( 759 )

A threedimensional slice gear model that takes modulus and tooth number as the variables was formulated,and Moldflow was used to establish the reasonable cooling and gating system and to analyze the gear model.The relationship curves between the two variables and the target parameter (maximum warping caused by shrinkage) were made. It was found that the target parameter value linearity increased with increasing number of teeth when the modulus kept constant.The tilt of each line was also different and the slope of straight line became greater with increasing modulus when the modulus kept different.The fitting curves was obtained with Matlab.

Synthesis and Application of Poly(methylphosphite bisphenol A ester) Oligomer Flame Retardant

2016, 30 (02): 83-87 ; DOI: 10.19491/j.issn.1001-9278.2016.02.017

Abstract ( 635 )

Poly(methylphosphitebisphenol A ester) oligomer(PMPBE) was obtained by melt condensation polymerization of methylphosphonous dichloride and bisphenol A. The structure of PMPBE and the properties of epoxy resin(EP)/PMPBE blends were characterized with Fourier transformed infrared spectrum(FTIR), nuclear magnetic resonance spectroscope, thermogravimetric analyzer(TGA), differential scanning calorimeter(DSC), vertical burning tester,limited oxygen index tester, and micro-scale combustion calorimetry. Adding 20 phr of PMPBE, the limiting oxygen index of EP was increased from 19 % to 27.6 % and the sample passed the UL94 V-0 rating, the heat release capacity and heat release rate reduced by about 27 %.TGA results showed that the char yield at 700 ℃ increased obviously compared with the neat EP. Moreover, PMPBE had little influence on the mechanical properties of EP.

Preparation of a Kind of Environmentally-friendly Plasticizer by Hexahydrophthalic Anhydride and C₁₀ Straight Chain Alcohols through Homogeneous Catalysis and Its Properties

2016, 30 (02): 88-94 ; DOI: 10.19491/j.issn.1001-9278.2016.02.018

Abstract ( 621 )

An environmentallyfriendly plasticizer dioctyl1,2cyclohexane dicarboxylate (DIDCH) was prepared with tetrabutyltitanate as a homogeneous catalyst.The effect of the molar ratio of decanoltoHHPA, amount of catalyst, reaction time and temperature on the esterification rate was studied and the optimum conditions was found as: the molar ratio decanol to HHPA of 2.8∶1, reaction time was 3 h, the reaction temperature was 200 ℃,dosage of catalyst was 1.5 % of the mass of hexahydrophthalic anhydride. The product was a colorless transparent oily liquid, the esterification rate could reach 99.48 %. Fourier transform infrared spectroscopy (FTIR) and GC-MS were used to determine the structure of DIDCH. When poly(vinyl chloride) (PVC) was plasticized with DIDCH, the yellowing time was 60 min, the glass transition temperature (Tg) was -8.91 ℃.

Control Method of Precision Injection Molding Based on PVT Properties

2016, 30 (02): 94-98 ; DOI: 10.19491/j.issn.1001-9278.2016.02.019

Abstract ( 802 )

This review covered the following four aspects: pressure-volume-temperature(PVT) relationship of polymer materials, the core principle in precision injection molding, polymer PVT tester, the online diagnosis and self-healing control of defects in the injection molding. The opplication of PVT relationship was introduced.

Study on Influencing Factors of Plasticizing Capacity of Injection Molding Machines

2016, 30 (02): 99-103 ; DOI: 10.19491/j.issn.1001-9278.2016.02.020

Abstract ( 1064 )

The plasticizing capacity of an injection molding machine was studied in three aspects:screw structure, operation parameters, and polymer species. The relationship among the screw type, speed, screw displacement, back pressure, temperature, materials, and plasticizing capacity was revealed.It showed that with increasing screw rotation speed and mold temperature, plasticizing capacity of injection molding machine increased. With increasing screw displacement and back pressure, the plasticizing capacity of injection molding machine decreased.

Injection Mold Design of Auto Parts Based on Moldflow

2016, 30 (02): 104-108 ; DOI: 10.19491/j.issn.1001-9278.2016.02.021

Abstract ( 832 )

The mold process of plastic auto boxes, including fill time, injection pressure, melt front temperature, cavitation, and weld line location were analyzed by Moldflow software. According to the simulation, a three-plate submarine gate injection mold was designed. The application of molds showed that the design was reasonable. Smooth motion and high-dimensional accuracy were realized.One may find no burr, weld marks, air pockets, and other defects on the surface of the parts.