Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Elastomers and Composites
Journal Basic Information
Journal DOI :
The Rubber Society of Korea
Editor in Chief :
Volume & Issues
Volume 38, Issue 4 - Dec 2003
Volume 38, Issue 3 - Sep 2003
Volume 38, Issue 2 - Jun 2003
Volume 38, Issue 1 - Mar 2003
Selecting the target year
Shrinkage in Injection Molded Part for Operational Conditions and Resins
Mo, Jung-Hyuk ; Chung, Wan-Jin ; Lyu, Min-Young ;
Elastomers and Composites, volume 38, issue 4, 2003, Pages 295~302
The amount of shrinkage of injection molded parts is different from operational conditions of injection molding such as injection temperature, injection pressure and mold temperature, and mold design such as gate size. It also varies depending on the presence of crystalline structure in resins. In this study, part shrinkage was investigated for various operational conditions and resins. Poly(butylene terephthalate) (PBT) for crystalline polymer, and polycarbonate (PC) and poly(methyl methacrylate) (PMMA) for amorphous polymers were used. Crystall me polymer showed higher part shrinkage by about three times than that of amorphous polymers. Part shrinkage increased as melt and molt temperatures increased, and injection pressure decreased. Part shrinkage decreased as gate size increased since the pressure delivery is mush easier for larger gate sizes. Part shrinkage at the position close to the gate was larger than that or the position far from gate. This phenomenon might be occur by difference of residual stress.
Preparation and Characterization of
Encapsulation by PMMA Core-Shell latex
Lim, Jong-Min ; Seul, Soo-Duk ;
Elastomers and Composites, volume 38, issue 4, 2003, Pages 303~315
Inorganic/organic composite particles were also synthesized by changing an initiator an it's concentration, concentration of an adsorbed surfactant, reaction temperature, and agitation speed in the presence of
adsorbed SDBS. The polymerization conditions were optimized according to the conversion of the core-shell composite particles. In the inorganic/organic core-shell composite particle polymerization,
absorbed surfactant SDBS of 0.5 wt % was prepared first and then core
was encapsulated by sequential emulsion polymerization using MMA, concentration of APS
to minimize the formation of new PMMA particle during MMA shell polymerization. The structure characterization of the inorganic/organic core-shell particles was verified by measuring the decomposition degree of
using HCl solution. It was found that
was encapsulated by shell PMMA due to having excellent dispersion in the epoxy resin, smooth surface distinctly from spindle shape, and broad particle distribution after the capsulation.
Flame Retardancy and Foaming Properties of the Waste-Polyethylene(W-PE)/Waste-Ethylene vinyl acetate copolymer(W-EVA) Blend Foams
Moon, Sung-Chul ; Jo, Byung-Wook ; Choi, Jae-Kon ;
Elastomers and Composites, volume 38, issue 4, 2003, Pages 316~325
The blends of waste-polyethylene (W-PE)/waste-ethylene vinyl acetate copolymer (W-EVA) with inorganic and phosphorous flame retardants (i.e., aluminium hydroxide, magnesium hydroxide, and so on) were prepared by melt mixing techniques at different compositions and foamed. The flame retardancy and foaming properties of the blends, limiting oxygen index (LOI), heat release rate (HRR), carbon monoxide yield (COY), total heat release (THR), effective heat of combustion (EHC), expandability and cell structure were investigated using cone calorimeter, SEM, LOI tester and polarizing microscope. When the composition ratios of the W-PE/W-EVA blends were 50/50 (w/w), and the ranges of the flame retardants contents were
, we could obtain foams with the uniform and closed cell, high expandability (1900 % or more), high LOI, and low HRR values. These results depend on crosslinking and loaming conditions, a char formation and smoke suppressing effect. Aluminium hydroxide had more effect in the increase of LOI than magnesium hydroxide, while magnesium hydroxide considerably affected the decrease of HRR and COY.
A Study on Vulcanization Reaction of Modified Rubber Blends Using Dynamic Differential Scanning Calorimetry
Lee, Seung-Hyun ; Ahn, Won-Sool ;
Elastomers and Composites, volume 38, issue 4, 2003, Pages 326~333
Even though many studies have been reported about rubber vulcanization, it is still remained difficult to find a quantitative relationship between the final states of vulcanized rubber and initial formulation or processing conditions. Dynamic differential scanning calorimetry (DSC) method is known as a comparatively easy method to research for the rubber vulcanization in both experimental and analysis. In the present research, a study on the vulcanization reaction of NR/CB composites modified by isoprene(IR) and chloroprene(CR) rubbers is carried out using dynamic DSC method. Thermograms with several different heating rates were obtained and analyzed using the Kissinger method. Analysis showed that the vulcanization reaction was progressed through the first order reaction mechanism. In addition, the reaction temperature was severely influenced by the kinds or rubber modifiers, in this case, more influenced by CR than by IR. Those effects were clearly verified in the values of activation energy. Kinds of carbon blacks, however, could hardly influence on the reaction mechanism.
A Study on the Affection of Frequency and Displacement for Nonlinear Viscoelastic Bushing Model
Kim, Sung-Jin ; Min, Je-Hong ; Lee, Seong-Beom ;
Elastomers and Composites, volume 38, issue 4, 2003, Pages 334~341
A bushing is a device used in automotive suspension systems to reduce the load transmitted from the wheel to the frame of the vehicle. A bushing is a hollow cylinder, which is bonded to a solid steel shaft at its inner surface and a steel sleeve at its outer surface. The relation between the force applied to the shaft and the relative deformation of a bushing is nonlinear and exhibits features of viscoelasticity. A force-displacement relation for bushings is important for multibody dynamics numerical simulations. For the nonlinear viscoelastic axial response, Pipkin-Rogers model, the direct relation of force and displacement, has been derived from Lianis model and the sinusoidal input was used fer Pipkin-Rogers model, and the affection of displacement with frequency change was studied with Pipkin-Rogers model.
Jet-Fuel-Resistant PVC Sealant Containing a Polyester Plasticizer
Nam, Byeong-Uk ; Kim, Seog-Jun ;
Elastomers and Composites, volume 38, issue 4, 2003, Pages 342~353
This work is about the development of jet-fuel resistant PVC sealant using a polyester plasticizer. PVC copolymer was compounded with adipic acid glycol(Songcizer P-3000) or DOP plasticizers. Fuel-immersed and non-immersed penetration, solubility, flow, and elongation by tensile adhesion of PVC compounds were measured. Penetration increase by fuel immersion and solubility of PVC compounds with adipic acid glycol polyester plasticizer were smaller than those of PVC compounds with DOP plasticizer. Elongation by tensile adhesion test of PVC compound containing 500 phr of Songcizer P-3000 decreased proportionally to the content of DCDP (dicyclopentadiene) base petroleum resin adhesion promoter. Calcium carbonate(
) filler inhibited the diffusion of fuel in all the PVC compounds and decreased the solubility of PVC compounds containing Songcizer P-3000.
Investigation of Bottom Cracks in the Carbonated Poly(ethylene terephthalate) Bottle
Pae, You-Lee ; Nah, Chang-Woon ; Lyu, Min-Young ;
Elastomers and Composites, volume 38, issue 4, 2003, Pages 354~362
The use of a petaloid design for the bottom of carbonated poly(ethylene terephthalate)(PET) bottles is widely spread. This study investigated the causes of bottom cracks. The tensile yield stress variations of PET according to the crystallinity and stretch ratio were examined, then the stretch ratio and strength in the bottom area of a blown bottle were analyzed. A crack test was also performed to observe the cracking phenomena. The distribution of the effective stress and maximum principal stress were both examined using computer simulation to seek the influence of the bottom design on crack. It was concluded that the bottom cracks occurred because of inadequate material strength due to the insufficient stretching of PET, plus the coarse design of a petaloid bottom. The stretch ratio at the bottom during bottle blowing should be higher than the strain hardening point of PET to produce enhanced mechanical strength. The cracks in the bottom of the PET bottles occurred through crazing below the yield stress. The maximum principal stress was higher in the valleys of the petaloid bottom than in the rest bottom area, and the maximum principal stress had a strong effect on the cracks.