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2013, Volume 27 Issue 07 Publication date: 26 July 2013 Previous Issue Next Issue

Recent research progresses in Poly (butylenes succinate)/starch composite

2013, 27 (07): 1-7; DOI: 10.19491/j.issn.1001-9278.2013.07.001

Abstract ( 222 ) PDF (0 KB)( 56 )

PBS/starch composite has a good performance in biodegradable characteristic. However, the poor interface compatibility results in poor mechanical properties. In recent researches, several methods are used to ameliorate the interface compatibility, such as the use of different type of plasticizer, coupling agent, or polyester-grafted starch. Modified starch nano-crystal is also added into PBS to improve its mechanical properties. The prospect of PBS/starch composite material is also pointed out.

Research Progress in Modification of Heat Resistance and Toughness of Benzoxazine Resin

2013, 27 (07): 8-13; DOI: 10.19491/j.issn.1001-9278.2013.07.002

Abstract ( 304 ) PDF (0 KB)( 68 )

In this paper, the progress in studies of modification of heat resistance of benzoxazine resin as a novel thermosetting resin at home and abroad in recent years was reviewed in terms of molecular structure design, inorganic particles modification, alloy or copolymerizati0n modification and synthesis of novel benzoxazine. The development trend of benzoxazine resin in the future will be forecasted．

Research Progress in Flame Retardants for Polypropylene

2013, 27 (07): 14-18; DOI: 10.19491/j.issn.1001-9278.2013.07.003

Abstract ( 286 ) PDF (0 KB)( 55 )

The research and development of some flame retardants for polypropylene such as hydrated metal compound flame retardants, phosphorus flame retardants, silicone flame retardants, intumescent flame retardants, and nanometer flame retardants were introduced in details in recent years. It was pointed out the advantages and disadvantages of intumescent flame retardants and nanometer flame retardants, and their development directions.

Amide-Based Cellulose Nanocrystals to Improve the Barrier Property of Ethylene - Vinyl Acetate Copolymer (EVA) Film

2013, 27 (07): 19-24; DOI: 10.19491/j.issn.1001-9278.2013.07.004

Abstract ( 337 ) PDF (0 KB)( 77 )

Three amide-based cellulose nanocrystals were synthesized, and the amide-based cellulose nanocrystals/ethylene-vinyl acetate copolymer (EVA) composite membrane materials were prepared by solution blending film-forming method. UV - visible spectrophotometer, electronic universal testing machine and water vapor permeability instrument were used to characterize the optical, mechanical and water vapor barrier properties of amide-based CNC/EVA composite films. The surface morphology of thermocompression treated EVA films was observed by atomic force microscopy. The results showed that the transmittance of EVA composite films can be decreased by adding three types of amide-based CNC, and the EVA composite film transmittance remained as high as 90% that the added amount of CNC up to 5%. Amide-based CNC can be dispersed in the EVA matrix more uniformly by a certain degree of thermocompression , so that EVA composite film transmittance can be increased by 2% ~3%. With the gradual increase of the content of CNC, three CNC/EVA film tensile strength are gradually increased, the WVTR values are reduced. Same amide-based CNC content, mechanical and water vapor barrier properties of Hexadecylamine modified cellulose nanocrystals (CNC-N16)/EVA films were better than that of dodecylamine and octylamine modified cellulose nanocrystals/EVA films.

Study on the β-Crystallization Behaviors of Homo-Polypropylene and Random Co-Polypropylene

2013, 27 (07): 25-32; DOI: 10.19491/j.issn.1001-9278.2013.07.005

Abstract ( 397 ) PDF (0 KB)( 70 )

The crystallization behaviors of homo-polypropylene and random co-polypropylene with and without nucleating agent were investigated comparatively by using differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WXD), and polarized optical microscopy (POM). The experimental results indicated that the faster the cooling rate of melted polypropylene was, the greater the content of β-polypropylene was, which was more obvious for homo-polypropylene than for random co-polypropylene. Meanwhile, it was found that homo-polypropylene with lower melting flow rate was more likely to form β-form crystallites. In the presence of β-nucleating agent, both homo-polypropylene and random co-polypropylene possessed greater number of spherulites, higher crystallization temperature, crystallization activation energy, the content of β-polypropylene and crystallinily, when compared with their pure counterparts. However, the influence of cooling rates on the content of β-polypropylene was reduced for both homo-polypropylene and random co-polypropylene after nucleating agents being added. Under the same circumstances of cooling rates of melt and content of β-nucleating agent, the homo-polypropylene always had higher crystallinity and content of β-polypropylene than the random co-polypropylene.

Influences of ATH and APP on Flame Retardant and Smoke Suppression Properties of Bamboo Flour/Polylactic acid Composites

2013, 27 (07): 33-37; DOI: 10.19491/j.issn.1001-9278.2013.07.006

Abstract ( 397 ) PDF (0 KB)( 82 )

Abstract: Bamboo flour and polylactic acid as raw materials preparation of bamboo flour/polylactic acid composites, flame retardant and smoke suppression properties of bamboo flour/polylactic acid composites were tested after treated with Aluminium Hydroxide (ATH) and Ammonium Polyphosphate (APP). The results show that two flame retardants both added char rate about 2 times of composites at high temperature, respectively has achieved 24.7% and 25.6%. ATH and APP both effectively enhanced flame retardant properties of composites. And APP is more obvious in inhibited heat release of composites in combustion process, but large amount of smoke. The effect of ATH on the inhibition heat release of composites is less than APP, but smoke suppression effect is obvious.

The Characterization and Performance Tests of Electrochemical Deposited Polythiophene Film

2013, 27 (07): 38-42; DOI: 10.19491/j.issn.1001-9278.2013.07.007

Abstract ( 537 ) PDF (0 KB)( 74 )

The polythiophene film were gathered directly in ionic liquid BFEE by electrochemical deposition. The doping state of turquoise polythiophene film 1# were get at 1.1 V constant potential, then get undoping state of vivid red film 2# by add 0.2V constant voltage at film 1#. Study the electrochemical performance of polythiophene film using cyclic voltammetry (CV) method, the result indicates that the polythiophene film get from ionic liquid BFEE has good electrochemical stability. Test the two different state polythiophene films’ resistivity through the electric transport test system, we get two sets of data of specific conductance corresponds to film 1# and film 2#, they are 44.64 S/cm and 1.33 S/cm. The specific conductance of doping stated film 1# is 33 times higher than undoping stated film 2#. This result in line with the conclusion that doping can improve the conductivity of polymer. And the data shows that this method of polymerize is good for it’s conductivity of the polythiophene film is fine.

Materials and Properties

The research of carbon fiber reinforced PPO/PA6 composities

2013, 27 (07): 43-47; DOI: 10.19491/j.issn.1001-9278.2013.07.008

Abstract ( 370 ) PDF (0 KB)( 78 )

Poly(2,6-dimethy-1,4-phenylene oxide)/polyamide 6/styrene ethylene butadine styrene copolymer/carbon fiber(PPO/PA6/SEBS/CF) composities were compatibilized by maleic anhydride (MAH) grafted PPO (PPO-g-MAH) and reinforced by carbon fiber (CF) via melt extrusion.CF was mixed through the side chipper spout，the content of CF can be controled by alter the speed of screw．Dynamic Thermal Mechanical Analysis（DMA），Capillary Rheometer and Mechanical Properties Testing were used to investigate the effect of CF content on thermal mechanical properties，rheological behaviors and mechanical properties of composities．Compared with the composities reinforced by glass fiber (GF) through Scanning Electron Microscopy (SEM) and Mechanical Properties Testing，the mechanical properties of composities and the adhesion of polymers to CF is better than GF．

The Influence of basalt fiber on the strengthening and toughening of HDPE/Bamboo composites

2013, 27 (07): 48-51; DOI: 10.19491/j.issn.1001-9278.2013.07.009

Abstract ( 458 ) PDF (0 KB)( 64 )

In this article, we prepared HDPE/bamboo/basalt fiber composites by melting blending method and investigated the influence of bamboo powder and basalt fiber on tensile strength, bend stength, impact strength and heat resitance of HDPE. The results have shown that bamboo powder leads to the decrease in tensile strength and impact strength, but the increase in tensile strength; when basalt fiber was added, the composites show a increase trend in tensile strength and bending strength, also, it improve the toughness. And it is a good reinforcing materials for wood / bamboo and plastic composites（W/BPC）.

Study on Creep properties and Crystallization of POB Filled PTFE Composites

2013, 27 (07): 52-56; DOI: 10.19491/j.issn.1001-9278.2013.07.010

Abstract ( 253 ) PDF (0 KB)( 95 )

Toughening Modification of Poly(butylene adipate-co-terephthalate) Copolymer on Poly(lactic acid)

2013, 27 (07): 57-61; DOI: 10.19491/j.issn.1001-9278.2013.07.011

Abstract ( 250 ) PDF (0 KB)( 52 )

PLA/PBAT blends with various loadings of PBAT and chain extender ADR were prepared by a twin-screw extruder at different processing conditions，including twin-screw speeds and die temperature. Phase morphology of the resultant blends were observed by SEM. And their impact properties were tested also. It is shown that the toughness of PLA was improved a lot with the addition of PBAT, and the fractured surfaces of PLA/PBAT with ratio of 85/15 exhibited roughened feature. The impact strength of PLA/PBAT(85/15)increased by 320%while the loadings of chain extender ADR is 0. 6%.With the increase of twin-screw speed，the impact strength of the blend increased，and reached its best value 0. 45 kJ/mz at the speed of 80 r/min.

Research on ultra-high molecular weight polyethylene crosslinked by gamma irradiation

2013, 27 (07): 62-67; DOI: 10.19491/j.issn.1001-9278.2013.07.012

Abstract ( 302 ) PDF (0 KB)( 55 )

In this paper, PE-UHMW sheets were extruded by single screw extruder and crosslinked by different gamma irradiation does thereafter. Effect of gamma irradiation does and treatment on properties PE-UHMW composites was studied. With a proper does of gamma irradiation, the gel content、melting point、crystallinity、surface hardness、tensile strength、heat distortion temperature and wear resistance of UHMWPE could be improved. Heat distortion temperature of UHMWPE was increased by 40 ℃ when the gamma irradiation does reached 150 kGy. But gamma irradiation crosslinking reduced its toughness. The tensile elongation at break decreased. Remlting could further increase the gel content and enhanced its toughness, but reducing the melting point, crystallinity, surface hardness, tensile strength.

Effects of Measurement Method on Fractal Dimension

2013, 27 (07): 68-72; DOI: 10.19491/j.issn.1001-9278.2013.07.014

Abstract ( 347 ) PDF (0 KB)( 78 )

In this paper, the fractal dimension were calculated for the tensile fracture surface of PVC / NBR blend thermoplastic elastomer by the island method and the box method, and the differences between the island method and the box method were analysized and compared. According to the calculated results, it indicated that the conclusions were consistent on revealing material microstructure and evaluating the evolution of material fracture,though the calculated results had some differences. In addition, only the proper and appropriate determination method for computing the fractal dimension was chosen, could the fractal characteristics, the material microstructure, the fracture evolution laws ,and the dynamic mechanics of fractal formation be revealed more true and more accurate.

Preparation and Application of Silane/Maleic Anhydride Grafted PE-HD

2013, 27 (07): 73-76; DOI: 10.19491/j.issn.1001-9278.2013.07.015

Abstract ( 473 ) PDF (0 KB)( 48 )

Silane/Maleic Anhydride Grafted PE-HD (MAH/VTMS -g-PE-HD) were preparaed with using silane and maleic anhydride as monomer, dicumyl peroxide(DCP) as initiator. The effect of silang(VTMS) and maleic anhydride(MAH) and DCP content on the properties of MAH/VTMS-g-PE-HD were investigated. The grafting was analyzed by FTIR and applied in composites. The results demonstrated that VTMS and MAH were successfully grafted onto PE-HD and the grafted degree increased firstly then decreased with increase of DCP, VTMS and MAH concentration. Compared with MA-g-PE-HD and VTMS-g-PE-HD, MAH/VTMS-g-PE-HD more efficiently improved the properties of composites.

The control of extrusion flow rate of SP system

2013, 27 (07): 77-80; DOI: 10.19491/j.issn.1001-9278.2013.07.016

Abstract ( 269 ) PDF (0 KB)( 70 )

Found out the two factors which influences the extrusion flow rate based on the comment of the working principle and process features of SP system. Analyzed the structural of barrel temperature, identified the model, designed the three input three output controller, took the model free adaptive control method ( MFAC ) to control temperature, and carries on the simulation; establish the extruder outlet pressure system model, on the basis of the establishment based on the HSIC MFAC cascade control structure of model, and take on Human-simulated Intelligent MFA control method of MFAC penalty factor is modified, the final simulation. According to the field measurement, display based on MFAC SP system process control, the control of the extrusion flow rate is accuracy and stable.

Effects of Rare Earth Myristate Compound Stabilizer on the Thermal Stability of PVC

2013, 27 (07): 81-85; DOI: 10.19491/j.issn.1001-9278.2013.07.017

Abstract ( 304 ) PDF (0 KB)( 55 )

Abstract：The rare earth stabilizers of lanthanum myristate, cerium myristate and neodymium myristate were synthesized. Novel rare earth myristate compound thermal stabilizers for rigid PVC were prepared from lanthanum (cerium/neodymium) myristate, zinc/calcium stearate, pentaerythritol and investigated by the Congo red method. Influence of these stabilizers on PVC was determined by means of torque rheometer process tests and dynamic mechanics spectrometer. The result showed that rare earth compound thermal stabilizers had good thermal stability. Static and dynamic thermal stability time could reach about 120 min and 60 min. The early coloring of PVC was restrained better. Processing performance of rare earth compound thermal stabilizers were better than lead salt system. The tensile strength, tensile strain at break and fracture strength were similar to lead salt system, while the impact strength was higher.

Study on the synergistic effects of polyols with calcium/zinc stabilizer complex

2013, 27 (07): 86-89; DOI: 10.19491/j.issn.1001-9278.2013.07.019

Abstract ( 330 ) PDF (0 KB)( 68 )

The synergistic effects of maltitol, mannitol, and pentaerythritol with calcium/zinc thermal stabilizer in PVC were compared using Congo red test, conductivity measurement, thermogravimetric analysis, thermal aging method. The results showed that the thermal stabilization time of PVC containing calcium/zinc complex with maltitol was 46 min, 4 times as that of pure calcium/zinc system. From the conductivity measurements the induction time of the system was longer up to 43.81 min. Moreover, the thermal weight loss in the first stage was 48.13% from the thermo gravimetric analysis. All the calcium/zinc complex systems with polyols used in this work showed the better long-term thermal stability than that with mannitol or pentaerythritol.

Optimization of Injection Molding Process and Quality Evaluation for Some Outer Decoration Parts Based on Orthogonal Test Method

2013, 27 (07): 90-93; DOI: 10.19491/j.issn.1001-9278.2013.07.020

Abstract ( 245 ) PDF (0 KB)( 87 )

The studied outer door is a plastic production with thin for the outer decoration of the certain type DVD disc recorder. And there are the higher requirements of assemble, appearance and so on. According to the warpage of part in the practical production, combining with orthogonal experiment method and CAE technology, the process parameters are optimized and the optimal combinations of process parameters are achieved by the integrated balance method. Especially, under this process, the qualified product can be obtained through the experimental verification. The research may provide a theoretical basis and technical support to the practical mass production.

Injection Mold Design and Mold Flowing Analysis for the front cover Based on UG

2013, 27 (07): 94-97; DOI: 10.19491/j.issn.1001-9278.2013.07.021

Abstract ( 378 ) PDF (0 KB)( 71 )

Through analyzing the technological features of the up-cover and the mold flowing of the mouse shell, used UG to design a injection mold . Introduced in detail design process of design parting surface, cavity layout, gating system, temperature control system, core-pulling mechanism and exhaust system about injection mould of the up-cover and working process of the mold.At the same time,we analyze the mold filling、fill and pack and cool with MoldFlow Plastics Insight(MPI).

Study on the Influence of Die geometric on extrusion PP foam

2013, 27 (07): 98-102; DOI: 10.19491/j.issn.1001-9278.2013.07.022

Abstract ( 244 ) PDF (0 KB)( 72 )

Abstract: Extrusion die is the key device in extrusion molding, a reasonable design of the die can ensure the quality and yield of products. A series of sheet dies were designed according to the qualification.The designed dies were utilized to do the foaming experiments, processing parameters were recorded during the experiment, and the foaming products were examined and tested, especially the influence of the die structure on the expansion ratio and foam structure of the polypropylene foams was discussed emphasisly. At last, the experimental results suggested that the height and length of the die channel were the main factors that influence the polypropylene foaming sheet.