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2015, Volume 29 Issue 05 Publication date: 26 May 2015 Previous Issue Next Issue

China Plastics Industry (2014)

2015, 29 (05): 1-4 ; DOI: 10.19491/j.issn.1001-9278.2015.05.001

Abstract ( 564 )

General situation of China plastics industry in 2014 was reviewed, including the output/export and import of plastics products, synthetic resins, 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 2014 was made, and the developing trend of China plastics industry in 2015 was proposed.

Research Progress of Transparent Polyimide Films

2015, 29 (05): 5-13 ; DOI: 10.19491/j.issn.1001-9278.2015.05.002

Abstract ( 881 )

Recent research and industrial production of colorless and transparent polyimide film were reviewed. Introduction of fluorine substituent, alicyclic moieties, non-plane conjugate structure, and sulfone moieties into the polyimide backbone constituted the main technology. Some in-depth research work was in the molecular design area. In the end, the development trend of colorless and transparent polyimide film was predicted.

Application and Development of Vitamin E as Antioxidants for Polymers

2015, 29 (05): 14-19 ; DOI: 10.19491/j.issn.1001-9278.2015.05.003

Abstract ( 453 )

The function of vitamin E in polymers as an antioxidant was discussed, as well as the feature, research, and market of the product. The antioxidant mechanism of vitamin E was analyzed.

Phase Morphology of Microinjection Molded PP/ABS Blends

2015, 29 (05): 20-24 ; DOI: 10.19491/j.issn.1001-9278.2015.05.004

Abstract ( 514 )

Two kinds of PP/ABS blend samples were prepared by conventional injection and microinjection moldings, the phase morphology and mechanical properties of the samples were compared by SEM. For the conventional injected samples, when the content of ABS was 40 wt%, the core layer gave rise to a co-continuous structure. When the content of ABS was 50 wt%, it became a dispersed phase of spherical particles. In the skin layer, the dispersed phase deformed seriously. For the microinjected samples, deformed largely caused by high shear rate. Moreover, the cooling was very fast, the morphology in the skin layer remained a co-continuous structure when the content of ABS reached 50 wt%, which was a result of stronger shear. The tensile strength decreased with increasing ABS content, and gave a low value when the co-continuous structure occurred.

Effect of Plasticizers on Properties of PA6

2015, 29 (05): 25-29 ; DOI: 10.19491/j.issn.1001-9278.2015.05.005

Abstract ( 748 )

Polyamide 6(PA6) was plasticized by glycerol diacetate (GP), polyethylene glycol (PEG), and triethyl citrate (TEC). TEC showed a different plasticizing behavior compared to the other two plasticizers at the same dosage. When the amount of TEC was 3 %, the tensile strength decreased slightly, the impact strength increased 6 times, while the crystallinity of plasticized PA6 decreasd 21 % compared to neat PA6.

Though Properties of Halogen-free Flame-retardant Long-glass-fiber-reinforced Polypropylene

2015, 29 (05): 30-33 ; DOI: 10.19491/j.issn.1001-9278.2015.05.006

Abstract ( 476 )

The influence of types and content of flame-retardants and glass fibers on the mechanical properties, glow-wire ignition temperature, comparative tracking index was investigated. It was shown that the comprehensive performance of composite containing a home-made halogen-free flame-retardant (OP1120A) was the best. Though the mechanical properties and the comparative tracking index decreased, the flame retardant properties increased with increasing OP1120A content. When the content of long-glass-fiber-reinforced was 40 % and the content of OP1120A was 17 %, the tensile strength, impact strength, comparative tracking index, and glow-wire ignition temperature of the composite were 189 MPa, 213 J/m, 650 V and 960 ℃ respectively.

Influence of Structure of Rubber Particles on Mechanical Properties of ABS Resin

2015, 29 (05): 34-40 ; DOI: 10.19491/j.issn.1001-9278.2015.05.007

Abstract ( 384 )

Several ABS copolymers were prepared via emulsion polymerization, which were melt-blended with SAN resin forming ABS/SAN blends. The effect of rubber phase structure on the mechanical properties of the blends was studied. It was found that the impact strength increased and tensile strength decreased with increasing rubber particle size. Moreover, the deformation mechanism transformed from pure crazing to shear-yielding of matrix induced by cavitation of rubber particles.

Study on Cure Kinetics and Thermal Stability of Rosin-based Epoxy Resin/Maleopimarate

2015, 29 (05): 41-46 ; DOI: 10.19491/j.issn.1001-9278.2015.05.008

Abstract ( 496 )

Maleopimarate (MPA) was synthesized from rosin and maleic anhydride by Diels-Alder reaction， which was used reaction with epichlorohydrin to synthesize rosin-based epoxy resin (MPAER). The dynamic mechanical property, cure kinetics, and thermal stability were characterized by DMA, DSC and TG. It showed that the glass transition temperature of cured MPAER was 53.2 ℃ when the mass ratio of MPAER with MPA was 5∶5, and the average curing activation energy (Eca) was 52.29 kJ/mol. When the heating rate was 10 ℃/min, the initial degradation temperature (Tid), was 211.9 ℃, the fast thermal degradation temperature was 347.7 ℃, and the final degradation temperature was 639 ℃。

Synthesis and Properties of Biferrocene with Organic Silicon Grafting HTPB

2015, 29 (05): 47-53 ; DOI: 10.19491/j.issn.1001-9278.2015.05.009

Abstract ( 548 )

In this paper, biferrocene 2, 2-di (ethylferrocene) propane-organic silicon was prepared as follows: 4-chlorobutyryl chloride was grafted on one end of 2, 2-di(ethylferrocene) propane by Friedel-Crafts acylation, which was reduced and coupled with dimethylchlorosilane. The product was further reacted with hydroxyl-terminated polybutadiene (HTPB) in the presence of platinum catalyst (silica-supported chitosan complex of chloroplatinic acid SiO2-CS-Pt). The structure of the product was characterized by 1H-NMR, FTIR, and TG. The grafting rate and hydroxyl value were also measured. It showed that with an iron content of 8.24 %, the initial and final thermal decomposition temperature of the product were lowered, and its thermal sensitivity and excellent catalytic performance for ammonium perchlorate were increased.

Rheological and Foaming Behavior of Chain Extended Poly(ethylene terephthalate)

2015, 29 (05): 54-59 ; DOI: 10.19491/j.issn.1001-9278.2015.05.010

Abstract ( 477 )

Poly(ethylene terephthalate) (CEPET) was chain extended with pyromelliticdianhydride (PMDA), which was foamed by batch method using CO2 as a foaming agent. Rheological behavior and cellular structure of CEPET foam were analyzed by rotational rheometer and scanning electron microscope. It showed that the storage modulus of CEPET was increased with increasing PMDA dosage, and the loss factor changed in an opposite way. The introduction of PMDA improved the melt strength and cellular morphology of neat PET. The expansion ratio of CEPET foam with a PMDA content of 1.0 phr was 32.55.

Preparation and Properties of PA6/Hydrotalcite Nanocomposites

2015, 29 (05): 60-64 ; DOI: 10.19491/j.issn.1001-9278.2015.05.011

Abstract ( 531 )

A PA6/hydrotalcite nanocomposite (PA6/MgAl-PMOBA-LDHs) was synthesized through in-situ polymerization. The property and structure of the resulted nanocomposite were characterized by TEM, UV spectrum, XRD, TG, and DSC, etc. The results indicated that the nano MgAl-PMOBA-LDHs uniformly dispersed in the matrix, and compared with pure PA6, the nanocomposite could strongly absorb the ultraviolet rays between 320~380 nm. XRD and DSC showed that a small amount of MgAl-PMOBA-LDHs played a good role in heterogeneous nucleation of PA6, and increased the crystallization temperature and crystallinity. The presence of a few exfoliated MgAl-PMOBA-LDHs had significantly contribute to the formation of gamma crystalline of PA6.

Fast Pyrolysis of Polystyrene to Obtain Styrene at High Temperature

2015, 29 (05): 69-69 ; DOI: 10.19491/j.issn.1001-9278.2015.05.012

Abstract ( 688 )

A fast pyrolysis process in a tubular reactor was proposed in this paper. Polystyrene was firstly dissolved in toluene and then fed into reactor in an atomized way. The effect of pyrolysis atmosphere, reaction temperature, and retention time on the pyrolysis was investigated. It showed that oil and styrene yield increased with increasing retention time. Styrene yield increased at first and then decreased with increasing reaction temperature, and the maximum styrene yield of 36.67 % was obtained at 890 ℃. Pyrolysis gas was mainly methane, ethylene and propylene and gas yield increased with increasing retention time and reaction temperature. Moreover, the addition of water vapor could reduce residual char. In addition, nozzle diameter had an obvious effect on oil and styrene yield.

Simulation of Liquid Silicone Reaction Injection Molding Based on DSC Experiments

2015, 29 (05): 70-74 ; DOI: 10.19491/j.issn.1001-9278.2015.05.013

Abstract ( 674 )

The reaction-curing curve of a kind of liquid silicone was determined with differential scanning calorimetry(DSC), from which the relationship between the curing degree and the curing rate was obtained. The reaction rate constants, reaction order, and activation energy were obtained. These parameters were used in the material library of Moldflow to simulate the reaction injection molding. The curing degree and injection pressure during the injection molding were obtained by simulation. The error between the simulation and actual injection pressure in production was about 10 %.

Effect of PVC Molecular Orientation on Plasticizer Migration Based on Micro-nano Lamination Technology

2015, 29 (05): 75-79 ; DOI: 10.19491/j.issn.1001-9278.2015.05.014

Abstract ( 354 )

Three kinds of PVC sheets with different orientation degree were prepared using a self-made micro-nano lamination device in this paper. The properties of the sheets had been characterized using scanning electron microscope, universal testing machine, density and thermal volatilization loss rate. Mechanical properties, density and heat loss rate test showed that: compared with the PVC sheets prepared without lamination device, along the extrusion direction the tensile strength of the sheets prepared with 2 and 4 lamination devices had increased by 5.72 and 10.18%, the density had increased by 2.81 and 4.35%, the volatilization loss rate had decreased by 13.12 and 37.65%, respectively.

Optimization of Residual Stress and Fracture Defect Analysis of Automotive Front Bumper Brackets

2015, 29 (05): 80-84 ; DOI: 10.19491/j.issn.1001-9278.2015.05.015

Abstract ( 638 )

This paper established a model for injection of large automotive parts with which the fracture defect analysis could be carried out to locate the fracture. The optimization goal was to determine the residual stress in fracture location. By orthogonal experiments, CAE analysis, and data processing technique, various factors influencing residual stress in fracture location, and the optimal combination of process parameters were obtained.

Oil-absorbing Polyurethane Foams Modifed by DOPO-HQ

2015, 29 (05): 85-88 ; DOI: 10.19491/j.issn.1001-9278.2015.05.016

Abstract ( 406 )

In this paper, a series of oil-absorbing polyurethane foam were prepared from polyether polyols, hydrophilic dihydric alcohol, triethylene diamine, DOPO-HQ, and toluene diisocyanate（TDI). The effect of DOPO-HQ content on the tensile strength, oil absorption, and flame retardant property was investigated. It showed that the tensile strength of the polyurethane foam first increased then decreased, oil absorption decreased with increasing concentration of DOPO-HQ. The limited oxygen index of the polyurethane foam increased from 18.2 to 27.2 % with the amount of DOPO-HQ increased from 0 to 12phr.

Enzymatic Degradation of Sisal Fibers Reinforced Polylactic Acid Composites

2015, 29 (05): 89-93 ; DOI: 10.19491/j.issn.1001-9278.2015.05.017

Abstract ( 299 )

Sisal fibers (SF) reinforced poly (lactic acid) (PLA) composites were prepared by hot-press molding. The bio-degradation performance of the composites was investigated by K- protease degradation, and the non-isothermal crystallization performance of PLA during enzymatic degradation was analyzed by differential scanning calorimetry (DSC). It showed that the introduction of sisal fiber into PLA matrix could accelerate the degradation rate of the composites, which increased with increasing SF weight fraction.

Domestic and Foreign Standards of Polyethylene Piping Systems’ Products for the Supply of Gaseous Fuels

2015, 29 (05): 94-100 ; DOI: 10.19491/j.issn.1001-9278.2015.05.018

Abstract ( 322 )

This paper introduced the status of domestic and foreign standards of polyethylene piping products for gaseous fuel supply. The domestic and foreign standards’ requirements of polyethylene (PE) pipes and fittings were compared. It was recognized that different standards have their advantages and characteristics. The requirements of International Standard (ISO) and European Standard (EN) are comprehensive and basically the same. The standards of American Society for Testing and Materials (ASTM) provide some innovative testing methods. Detailed requirements of products are described by the Standards Australia and Standards New Zealand (AS/NZS).

Design of Large and Thin-walled Injection Mold for Car‘s Front Bumpers

2015, 29 (05): 101-105 ; DOI: 10.19491/j.issn.1001-9278.2015.05.019

Abstract ( 477 )

A large thin-walled injection mold for car front bumper was designed, using the technology of inside parting surface and sequence valve gate control. Through analysis and research of the gating system, molding parts, side parting and pulling mechanism, the temperature control system, oriented positioning system, and ejection system, an advanced, reasonable, and safe mold structure was obtained.

Injection Mould Design of Telephone Receiver

2015, 29 (05): 106-110 ; DOI: 10.19491/j.issn.1001-9278.2015.05.020

Abstract ( 449 )

It analyzes the structure of the shell plastic part of the telephone receiver and molding process. Aiming at the characteristics of the front shell and rear cover plastic parts of the receiver including matching production, thinner wall, more stiffener, undercutting and high requirement on the surface quality, it designs the mould for the molding matching plastic part with the single injection. And, it applies the combination of the moving and fixed die inserts, the compound inside and outside entrant demoulding of the slider angle pin and swing rod, open model in order and ejector mechanism of different forms. Meanwhile, it introduces the design of main molding parts, mould gating system, vertical parting core pulling and ejector & reset mechanism. The practice indicates that the mould has the compact structure with the stable and reliable movement. The design planning is reasonable.