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2016, Volume 30 Issue 01 Publication date: 26 January 2016 Previous Issue Next Issue

Research Progress of Chemical Modification of Aromatic Polycarbonate

2016, 30 (01): 1-6 ; DOI: 10.19491/j.issn.1001-9278.2016.01.001

Abstract ( 637 )

In this paper, the research work of processing ability, optical performance, thermal behavior, mechanical properties, flame retardant, and solvent resistance of aromatic polycarbonate was reviewed. The effect of the structural unit of aromatic polycarbonate on its properties was discussed. The future trend of the polycarbonate was prospected.

A Review on the Progress of 3D Printing Materials

2016, 30 (01): 7-14 ; DOI: 10.19491/j.issn.1001-9278.2016.01.002

Abstract ( 649 )

The current 3D printing materials were categorized to two types: organic and inorganic materials, the former included acrylonitrile-butadiene-styrene copolymer, poly(lactic acid), polyamide resin, photosensitive resin and hydrogels; the latter included titanium alloy, ceramics, gypsum, etc. Furthermore, efforts were made on summarizing properties, advantages, and disadvantages of different types of 3D printing materials. The developing trend and perspective of 3D printing materials were also discussed.

Research Progress in Element Hybrid Flame-retardant Acrylic Resin

2016, 30 (01): 15-21 ; DOI: 10.19491/j.issn.1001-9278.2016.01.003

Abstract ( 509 )

In this article, recent research progress in flame retardant mechanism of acrylic resin was reviewed.The thermal decomposition and flame retardant process of acrylic resin were briefly introduced. The technology of introducing hybrid elements into acrylic resin was presented. Finally, the development of element hybrid flame-retardant acrylic resin was prospected.

Preparation and Performance of Composite of Nanosilica/Poly(methyl methacrylate-co-styrene)

2016, 30 (01): 22-27 ; DOI: 10.19491/j.issn.1001-9278.2016.01.004

Abstract ( 499 )

Nano-SiO2 was modified with a coupling agent (KH-570), and was mixed with methyl methacrylate and styrene. The system was subjected to a suspension polymerization leading to P(MMA-St)/nano-SiO2 composites, in which Nano-SiO2 was evenly dispersed in the matrix. The structure and properties of the composites were characterized using Fourier transform infrared spectroscopy, gel permeation chromatography, thermal gravimetric analysis, TEM, universal testing machine, and torque rheometer. Because of the interaction between nano-SiO2 and P(MMA-St),the molecular weight became larger, and the molecular weight distribution became narrow. Thermal stability and mechanical performance of the composites were significantly improved.

Effect of Modified Attapulgite on the Extraction of Plasticizers in Flexible Poly(vinyl chloride)

2016, 30 (01): 28-33 ; DOI: 10.19491/j.issn.1001-9278.2016.01.005

Abstract ( 520 )

Nanoparticles of attapulgite were first treated with a silane coupling agent, and further with steric acid. The modified attapulgite was characterized with Fourier transform infrared analysis (FTIR), contact angle tests, BET, and thermogravimetric analysis. Such attapulgite was introduced into plasticized poly(vinyl chloride) (PVC) systems by melt blending. It was found that the addition of attapulgite reduced the extraction of dioctylphthalate (DOP). Because its good compatibility with PVC, attapulgite also enhanced the mechanical properties of PVC.

Study on Mechanical Properties of PLA/PBS Toughening Blends Under Tensile Deformation

2016, 30 (01): 34-38 ; DOI: 10.19491/j.issn.1001-9278.2016.01.006

Abstract ( 657 )

Poly(lactic acid)/poly(butylene succinate) (PLA/PBS) and additives were melt blended in a vane extruder, the effect of composition and rotating speed on the mechanical properties was studied. With increasing PBS content, the tensile strength was little changed, while the impact strength increased significantly. When the rotating speed was 75 r/min, DCP content was 0.05 %, content of maleic anhydride grafted PP was 1.5 %, the mechanical properties was the optimal. SEM photographs showed that PLA was poorly compatible with PBS, however, the tensile force field provided by the vane extruder made the dispersed phase finer and more uniform.

Thermal Performance and Crystallization Behavior of Polyamide 6/Acrylate Rubber (ACM) Blends

Xiu-Yan REN

2016, 30 (01): 39-44 ; DOI: 10.19491/j.issn.1001-9278.2016.01.007

Abstract ( 781 )

Polyamide 6/acrylate rubber (PA6/ACM) blends were prepared by melt processing, and the thermal performance, crystallization behavior, and crystal morphology of the blends were investigated by differential scanning calorimetry (DSC), wide angle x-ray diffraction (WAXD), and polarizing microscope (PLM). It was found that with increasing ACM content, the melting point Tm and crystallization temperature Tc of the blends decreased slightly, the crystallinity and crystal size decreased. Upon addition of ACM into PA6, crystal phase transformation of γ→α occurred. Notched impact strength of PA6/ACM was significantly improved with increasing ACM.

tudy on Thermal Behavior and Dynamic Mechanical Properties of Highly Impact Polypropylene Copolymer with High Flowability

2016, 30 (01): 45-51 ; DOI: 10.19491/j.issn.1001-9278.2016.01.008

Abstract ( 489 )

Three kinds of high flow ability and impact copolymer polypropylene were characterized using differential scanning calorimeter, thermogravimetric analyzer and dynamic mechanical analyzer. It was found that the width of half height of crystallization for HHP10 was narrower, the crystallization rate was larger, the quantity of stereo-defects was greater, and the oxidation induction time was obviously shorter than AP03B and K7726. The heat resistance of 7726 was superior to and the samples HHP10 and AP03B. AP03B possessed the highest glass transition temperature, best impact strength. The compatibility of polypropylene matrix and ethylene propylene rubber in K7726 was the best. HHP10 gave the best storage modulus and rigidity.

Flame Retardant Modification of Poly(butylenes succinate)/Starch Blends

2016, 30 (01): 52-55 ; DOI: 10.19491/j.issn.1001-9278.2016.01.009

Abstract ( 545 )

Ammonium polyphosphate (APP), melamine (MA), starch, and glycerol were introduced into poly(butylene succinate) (PBS) forming a flame retardant composite. Influences on the combustion behavior and mechanical property of PBS were analyzed. The optimal properties of the composites were achieved when glycerin gelatinized starch was 20 %, the mass ratio of PBS and starch was 3∶1, flame retardant content was 24 %, and the mass ratio of APP and MA was 5∶1.

Preparation of Ultra-light Micro Foam TPU Particles by Supercritical CO₂ Batch Method

2016, 30 (01): 56-60 ; DOI: 10.19491/j.issn.1001-9278.2016.01.010

Abstract ( 531 )

This article introduced the preparation of ultra-light TPU granules through batch foaming by supercritical fluid. The effect of foaming temperature, saturation time, and saturation pressure on the density and performance of TPU granules was studied. It showed that the foaming temperature and pressure constituted the main factors influencing the particle cell structure distribution. When the saturation pressure and temperature were 11 MPa and 145 ℃, respectively，the foamed TPU granules possessed low density, big size，large and uniform porosity.

Crystallization and Rheological Behavior of Copolyesters Modified by Trimethylolpropane

2016, 30 (01): 61-67 ; DOI: 10.19491/j.issn.1001-9278.2016.01.011

Abstract ( 526 )

Copolyester (BPET) modified with trimethylolpropane (TMP) was prepared through direct esterification and melt polycondensation method. Their structure and properties, crystallization and rheological behaviors were characterized. With TMP content increasing, the half crystallization time of BPET became longer and the melt crystallization peak temperature decreased. The non-Newtonian index of BPET melt became smaller and the dependence of the apparent viscosity on shear rate increased. The viscous flow activation energy of BPET at the experimental shear rates was lower than that of polyethylene terephthalate, so it would not be suitable to improve BPET’s flowability by rising temperature.

A Comparative Study on Morphology,Crystallization Behavior,and Mechanical Properties of Three Types of PLA/OMLS Nanocomposites#br#

ZHANG Yuxia, WANG Xingguang, WANG Xiangyu, ZHOU Peng

2016, 30 (01): 68-74; DOI: 10.19491/j.issn.1001-9278.2016.01.012

Abstract ( 76 )

Optimization of Gating System for Injection Molded Inserts Based on Moldex3D

2016, 30 (01): 75-79 ; DOI: 10.19491/j.issn.1001-9278.2016.01.013

Abstract ( 591 )

The melt flow process of insert molding for thin-walled model which had different number of gates was simulated using the specialized software Moldex3D. Temperature and pressure distribution, comparative analysis weld marks and other evaluation parameters were used to evaluate the influence of gating system, finally the best solution for the inset molding was achieved.

Strain Rate and Temperature Sensitive Properties of Carbon Fiber Reinforced Thermoplastic Composites

, Xue-Qian SONG

2016, 30 (01): 80-85 ; DOI: 10.19491/j.issn.1001-9278.2016.01.014

Abstract ( 901 )

The tensile behavior of carbon fiber reinforced poly(ethylene terephthalate) was studied at strain rates from 0.001 s-1 to 50 s-1 and temperatures from -40 ℃ to 80 ℃. The tensile strength increased with increasing strain rate, and decreased with increasing temperature. In contrast, the failure strain increased with increasing temperature.

Influences of Three-screw Extruders’ Shear-tensile Alternating Flow Field on Toughening Effect of PP/PE-HD Blend Systems

2016, 30 (01): 86-91 ; DOI: 10.19491/j.issn.1001-9278.2016.01.015

Abstract ( 555 )

Effect of shear-tensile alternating flow field on the dispersive and distributive mixing performance of high viscosity ratio blend systems was studied using a series of PP/PE-HD blends with different viscosity ratio in a triangle arrayed three-screw extruder and a traditional twin-screw extruder. It showed that the three-screw extruder gave better dispersive and distributive mixing performance for high viscosity ratio composite systems than those of the twin-screw extruder, and the toughening effect was enhanced with increasing viscosity ratio of the blend systems.

Preparation, Structure and Properties of PVA/CuSO₄·5H₂O Membranes

2016, 30 (01): 92-97 ; DOI: 10.19491/j.issn.1001-9278.2016.01.016

Abstract ( 661 )

Poly(vinyl alcohol) (PVA)/CuSO4·5H2O membrane was prepared by solution casting. The structure and properties of the membrane were investigated by scanning electron microscope, thermogravimetric analysis，X-ray diffraction, mechanical testing, and gas permeability testing. After introducing Cu2+ ions into PVA, bonding between Cu2+ and PVA chains may be formed and therefore reduce the crystallinity of the membranes. The membrane possessed higher tensile strength and lower elongation at break compared with neat PVA membrane. The cross-linking of CuSO4·5H2O markedly improved the mechanical properties of the membrane. Under 75 % relative humidity，the addition of Cu2+ to PVA membranes resulted in dramatical improvement of CO2 permeability coefficient, while the O2 permeability coefficient almost did not change.

Study on Application of N-P-S Intumescent Flame Retardant in Polycarbonate

2016, 30 (01): 98-103 ; DOI: 10.19491/j.issn.1001-9278.2016.01.017

Abstract ( 490 )

A flame retardant (NPS) was added to polycarbonate (PC), and the flame retardant performance and thermal stability of the resultant PC composite were studied through limiting oxygen index and vertical burning, thermo-gravimetric analyzer (TGA), and cone calorimeter instrument. When the NPS loading was 0.075 %, the limiting oxygen index reached the maximum 37.5 %, vertical combustion grade reached V-0 level. NPS decreased the initial decomposition temperature of PC from 419.7 to 389.0 ℃, the carbon residue rate increased from 15.26 % to 20.8 %, at the same time the heat release rate (HRR) and total heat release (THR) were also reduced.

Thermal Stabilization Effect of Zn/Ca Adipate with Nano-CeO2 or La2O3 on PVC/ASA Blend

2016, 30 (01): 104-108 ; DOI: 10.19491/j.issn.1001-9278.2016.01.018

Abstract ( 559 )

Nano-CeO2 or La2O3 was introduced into znic/calcium adipate system as a co-stabilizer for PVC/ASA blends. The thermal stbility of resultant PVC/ASA blends was investigated by Congo red method and thermogravimetric analysis. The dynamic mechanical properties were also investigated. It was found that the thermal stability of PVC/ASA blends was enhanced when the rare earth compounds were used. The synergistic effect of lanthanum oxide with metal soaps was better than that of nano-cerium oxide. Moreover, the thermal distortion temperature of the blends was increased when nano-cerium oxide was added.

Velocity Uniformity of Tire Compounds at the Outlet of Flow Channel Based on Finite Element Analysis

2016, 30 (01): 109-114 ; DOI: 10.19491/j.issn.1001-9278.2016.01.019

Abstract ( 436 )

It is important for the quality of tire products to ensure the velocity uniformity of tire compounds along the width at the outlet of flow channel during extrusion. In order to investigate the influential factor of the velocity uniformity based on the optimized flow channel structure, the velocity, wall shear stress, and pressure fields are analyzed by a numerical simulation with CFD software Fluent. It showed that the velocity uniformity at the outlet was influenced by the viscosity and pressure of the tire compounds, but hardly affected by the change of temperature.

Study on Four-platen Injection Compression Clamping Units for Injection Molding Machines

2016, 30 (01): 115-119 ; DOI: 10.19491/j.issn.1001-9278.2016.01.020

Abstract ( 573 )

In this paper, a new type of four-platen injection compression clamping units was presented. The first mold closing was actived by the toggle mechanism, and the second was achieved by the pressurized plate. This clamping unit could improve the accuracy of mold closing. Simulations on the pressurized plates and movable plates were carried by finite element analysis software. The simulation showed that the stress and deformation of the pressurized plate and movable plate were limited to the allowable range of clamping units. The stress and deformation were uniformly distributed in the plates, which could improve the forming precision of products.