ZHU Xin-jun, WU Wei一dong, ZHANG Sheng
Abstract (
2079 )
The recent development of flame retardant polyethylene(PE) has been reviewed.The generic flame retardant systems employed in polypropylene have been categorized as four types: halogen-containing, inorganic compound，intumescent flame-retardant(IFR )，and nanocompositc. The halogen-con-twining type is represented by halogen-antimony, bromine-phosphorus, and bromine-boron synergic systans. Magnesium hydroxide, aluminum trihydrate and their synergic flame retardant arc typical inorpanic systems. T}etailed discussion was also made for chemical and physical intumescent，nano一structurcd materials, and silicon-containing flame retardants.
LI Bing, ZHOU Nan-qiao, WU Qing-feng
Abstract (
3166 )
Batch and continuous extrusion processing methods in open-cell foaming with inert gases as physical blowing agents arc summarized. Temperature, pressure, time and blowing agents concentration in foaming processing are important factors on the open-cell structure. The basic principles conformed in these different processing methods arc presented.Some factors influencing the behavior of opening and methods increasing open-cell content are analyzed. It was proposed that the electromagnetism dynamic processing will be one of the major methods in the open-cell foaming.
WANG Xiao-ting, TANG Sony-chao, PAN Yong-kang, WANG Qing-hai
Abstract (
2892 )
Glycidyl mcthacrylatc(GMA)and styrene (St) melting grafted [PE-LLD-g-(GMA-co-St)]was used as a reactive compatibilizer in PLA/PE-LLD) blends, which were characterized by
FTIR, dynamic rhcological test，SEM, and mechanical properties. With the addition of PE-LLD-g-(GMA一co-St)，the Charpy impact strength of the blends increased by 144 % based on plain PLA/PE-LLD blends. In addition, the loss modulus of the blends increased，the particle size of PE-LLD in PLA decreased，both indicating a good compatibilization.
GE Qiang, DING Xue-jia, ZHANG Hong-juan, WU Si-zhu, YANG Xiao-ping
Abstract (
2607 )
Poly(ethylene terephathalatc)(PET)was blended with poly(trimcthylcnc tcrcphthalatc)(PTT) via melt blending. The thermal，dynamically mechanical and tensile properties of PET/PTT blends were investigated by DSC, DMA,and tensile test. It shows that PET/PTT blends possess an excellent compatibility in amorphous phase. The To of neat PET and PTT is 84 and below 50℃，the melting points arc 256℃and 229℃，respectively. The chain segments of PET and PTT tend to crystallize separately in crystal phase corresponding to the appearances of two melting peaks and the width of the peak. Tensile modulus and tensile strength of blends increased with ascending PTT content. However, tensile modulus and tensile strength of blends decrease with the blend ratio approaching 0.5.The minimum tensile modulus and tensile strength of PET/P"IT blends arc 1098 MPa and 51 MPa, respectively.
ZHONG Liu, LIU Zhi-Guo, OU Yu-xiang
Abstract (
2957 )
hina
Abstract:Composites of polycarbonate/acrylonitrile-butadiene-styrene copolymer (PC/ABS)，Pc/APS/organic montmorillonitc (OMMT)，and PC/nBS/organic-modified nano-SiO2(SiO2)flame retarded by bisphcnol A di(phosphatc phenyl ester)(BDP) were prepared via extrusion and granulation using a twin-screw extruder. By means of TG，their thermal decomposition kinetic behaviors in nitrogen atmosphere were studied. Before 8 % mass loss, the activation energy of the PC/ABS/BDP/OMMT and PC/ABS/BDP/SiO2 nancomposites was lower than that of PC/ABS/BDP. However the opposite was observed after 8% mass loss. The average activation energy of PC/ABS/BDP/OMMT and PC/ABS/BDP/SiO2 were 139.39 kJ /mol and 144.17 KJ/mol in 5一75 % mass loss, respectively, all greater than that of PC/ABS/BDP(104.87 kJ/mol).It was found that with OMMT or SiO2 added，the thermal dccomposition speed of PC/ABS/BDP decreased and the thermal stability increased，as confirmed by the measurements of TG，limiting oxygen index, and UL94 V flame retardancy.
WU Yang, LUO Yan, HAN Jing
Abstract (
2027 )
Effects of MeTHPA/THPA weight ratio on particle size and particle size distribution of epoxyresin microspheres were studied. It showed that with the increasing MeTHPA/THPA weight ratio in the system, the domain size, particle size and monodispersity index of epoxy resin microspheres decreased gradually. When MeTHPA was used alone, epoxy resin microspheres with particle size of 4μm and monodispersity index of 1.1553 were obtained.
WANG Yue-xin, WAND Zhi一ling, ZHANG Qian
Abstract (
3873 )
Quadripolymer of tris(monododecy ester maleate)lanthanum，N-cyclohexyl-malcimide，styrene，and methyl methacrylate was synthesized via emulsion copolymerization and employed in PVC to improve its heat resistance. When the amount of LaTM and N-cyclohexylmalcimide in copolymer was 5 and 9.5 wt %，respectively, and the loading of quadripolymcr in PVC was 20 wt%，the Vicat softenink temperature，the 1 % and 50 % weight loss temperature of the blends increased 4. 7℃，32.64℃，and 17 .31℃based on neat PVC，respectively. In addition，the tensile and impact strengths of the blends increased 3.35 % and 1.62 %，respectively.
HAN Xiang-yan
Abstract (
2040 )
In this work, the interfacial tension between PA6/PP was studied by combining the breaking thread and the deformed drop retraction methods. The retraction behavior of polyamide 6(PA6) drops in polypropylene(PP) was on-line investigated，and the effect of compatibilizers on the interfacial tension between PP/PA6 was explored .It showed that the PA6 drops deformed under shear flow, and then retraded to spheroid under interfacial tension. The interfacial tension was 7.16 mN/m for PP/PA6 blends and decreased with introduction of the compatibilizer. The interfacial tension of different blends was in
the following order:γPP/PA6 > γPP/SEBS/PA6 > γPP/PP-g-AA/PA6 > γPP/PP-g-MAH/PA6
ZHENG Bao-ming
Abstract (
1921 )
Sodium methacrylate was grafted onto acrylonitrile-butadiene-styrene copolymer(ABS)in melt .The effect of monomers concentration，initiator concentration，reacting time, and temperature on grafting rate was studied. The performance of grafted ABS was researched by TG，oxygen index instrument，and mechanical property measurement. The optimal grafting condition was di(isopropyl benzene)peroxide (DCP) 0.4mol/L，reacting time 2 h, and reacting temperature below 120℃.The grafted ABS exhibited enhanced flame retardant performance, with little cost of mechanical properties. The grafting also improved the compatibilization between ABS and dccabromodiphcnyl oxide/antimony trioxide system.
YIN Hai一ying, BAI Yu, YANG Ming-bo, XU Peng-fei, FU Xiao-rong
Abstract (
1986 )
Via the numerical simulation coupled with experimental measurements, high-density polyethylene(PE-HD)and polypropylene(PP)were melt-blended in the following percentages of E-HD by weight:0，25，50，75，100 and injected in the injection molding. Under some assumptions,the temperature profiles arc numerically solved through the mathematical software package Matlab. The relationship between the percentages of PE-HD by weight and the values of the thermodynamic parametern is also concluded in the article. The model was tested by measuring the temperature profiles in a slab mold instrumented with a thermocouple. Measurements of temperature profiles show good agreement with the numerical prediction during the liquid cooling stage as well as the phase change process, where-as the theoretical values arc a bit larger than the experimental ones.
SONG Yan-jiang, ZHANG Gang, LAI Yu-mei, WANG Xiao-dong, HUANG Pei
Abstract (
2981 )
The thermoplastic polyimidc(TPI)/carbon fiber(CF)composites were prepared using a twin-screw extruder. The effect of molding methods(injection and compression molding) on the propertics o f the composites was investigated.The results indicate, compared with the compression molding method，the injected composite possessed better mechanical properties. The injection molded specimen showed lower coefficient of linear expansion in machine direction. However, the injected specimen had higher friction coefficient and wear rate. Furthermore, making the use of the stress-strain curves and the scan electronic microscope photos of fracture surfaces, the working mechanism was analyzed.
LIN Yuzn-zhi
Abstract (
2852 )
The protecting film for raw rubber sheets was prepared via three-layer co-extrusion blowing.PE-HD /PE-LD)(1/1 to 2/1)containing 1.5%一2.0% antiblock agent and 3.0%一3.5% anti-UV agent were used in the skin layer. The core layer was composed of metallocene PE，PE-LLD, recycled PE，and filler at weight ratios of 30/20/40/10.The obtained protecting film possessed excellent barrier propcrties.
FANG Hong-xia, ZHANG Lei, PAN Jian
Abstract (
3142 )
Cellulose, lignin，and starch were solution blended in a solvent N-methyl-morphine-oxide(NMMO) and a composite film was obtained. The surface morphology of the composite film was observed with AFM and SFM. The crystalline structure and mechanical properties of the film were also investigated. Because of the homogeneous phase structure formed as a result of the rearrangement of the natural polymer molecules, the film showed good mechanical properties, the different natural components exhibited mutual supplements.
SHEN Xiong-jun, ZHOU Zhong-cheng, SHU Wang-Gen
Abstract (
2941 )
Comparing with zinc stcarate, the thermal and weather stabilization effect of glyzinc compound (glyzinc for short) for PVC was investigated by Gongo red，heating aging, and rhcometer experimenu. The synergistic effect of glyzinc compounding with epoxy soybean oil and triphenyl phosphitc was investigated. When the weight ratio of glyzinc compounding, calcium stcarate, epoxy soybean oil，and triphcnyl phosphitc was 1.0 /1.5 /0.2 /0.2，and the loading of the compound stabilitizcr in PVC was 2. 9 phr, excellent thermal stabilization was obtained.In addition, the synergistic effect among zinc stcarate, calcium stcarate, epoxy soybean oil，triphcnyl phosphitc was also observed.
CUI Jin-hai, SHI Zhao-Zhong, JI Xue-Liang
Abstract (
3123 )
A flame retardant，10，10'-(5H，5H)-Spirobiphenophosphazinium chloride was prepared，its effects on the flame retardance and mechanical properties of ABS/Al(OH)3 composites were explored via regressive analysis of the data from a uniform design experiments using SPSS software. When the weight ratio of ABS, 10，10'-(5H，5H)-spirobiphcnophosphazinium, and Al(OH)3 in the composite was 100 /22 /18，excellent comprehensive properties were obtained.The notched，non-notched impact strengths, and tensile strength were 9.02KJ/m2 2.80 MPa, respectively. The oxygen index was 26. 1，horizontal firing ranked I，and vertical firing ranked FV-0.
WU Cheng-bao, LIANG Ji-zhao
Abstract (
3564 )
The impact and tensile strengths of hollow glass bead filled polypropylene(PP/HGB) were measured using Charpy impact tester and universal test machine. The relationship between the HGB size distribution and the mechanical properties was analyzed by means of grey relational rule. The results indicatcd that the volume fraction of particles with size range from 100.60 to 256.00 μm had major effect on the mechanical properties of PP/HGB composite. Those from 24.72 to 256.00 μm may improve the tensile properties but weaken the impact strength, however, those below 27.72μm may weaken the tensile properties but enhance the impact strength.
LENG Chong-jie, XIANG Hui-yu, SONG Shao-na, CHENG Jian-pu
Abstract (
2732 )
n order to investigate the application of numerical simulation in the mould conceptual design and process determination for the plastic injection process, the role and technical routine of computer aided engineering(CAE)in plastic injection mould design and related process planning was discussed based on a practical case. The assessment and optimization method of this technique for flow runner and cooling system design were introduced. The approach of using CAE technique for injection plan design during mould design stage is presented. It showed that this method could effectively predict the rationality of filling pattern and the potential defects caused by the improper mold design and injection process,determine air trap location，configure the cooling system and evaluate its rationality, and thus an effective way to shorten mould design cycle and improve mould design quality.
XIAO Fang-cheng, OU Xiang-lin, hU Hai-tao, WU Shi-jian
Abstract (
3224 )
The mechanism of weld line formation in LCD TV underprops molded by traditional runner system was analyzed. In a novel design of runner system, the melt would pass two gates and meet in a second runner and subsequently fill the mould in the form of an expansion flow. The melt flow process in the molding of LCD TV underprops was analyzed using Moldflow software. It was found that the novel design could effectually avoid the weld line formation in the products.
