• Korean Journal of Veterinary Research
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• v.43 no.4
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• pp.703-708
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• 2003

This study was carried out to compare the efficacy of carboxymethyl chitosan fabric (CMCF) with that of the combination of low molecular weight heparin (LMWH) and CMCF for the prevention of postoperative adhesions in the rat. Adhesions were induced by suturing both the ileal serosa and peritoneum scraped until petechial bleeding occurred. CMCF were sutured between two surfaces, and LMWH were instilled intraperitoneally immediately before closure of the peritoneomuscular layer. The adhesions were blindly assessed 2 weeks later by using a tensiometer. The mean tensile strength(Newton) of formed adhesions was $2.59{\pm}0.85$ in control group, $2.10{\pm}0.75$ in the CMCF group and $1.53{\pm}0.44$ in the CMCF+LMWH group. The most favorable prevention against adhesion was achieved in the CMCF+LMWH group. Therefore, we could conclude that CMCF+LMWH were effective in prevention against postoperative adhesion in the rat.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.379-383
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• 2007

This study was performed to compare the effects of carboxymethylcellulose (CMCE), chondroitin sulfate (Chondron), and carboxymethylchitosan (CMCH) on preventing intraperitoneal adhesion. As a result, the tensile strength of adhesions formed between the parietal peritoneum and the ileal serosa was significantly decreased in the groups of three different kinds of anti-adhesive agents. The distance of adhesion site was slightly increased in the treatment groups comparing control group. In the CMCH group, the inflammatory cell infiltration, collagen hyperplasia, and neovascularization were significantly lower than those of control group. It was observed that the damage at intestinal serosa was significantly decreased in the chondron and CMCH groups comparing control group. Therefore CMCH may be useful as a anti-adhesive agent in the prevention of intraperitoneal adhesion in rats.

• Journal of Adhesion and Interface
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• v.24 no.3
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• pp.86-94
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• 2023

To fabricate all-solution-processed flexible Organic Light-Emitting Diodes (OLEDs), we demonstrated a bonding technology using a polyethyleneimine (PEI) as an adhesion layer between the two substrates. As the adhesion layer requires not only a high adhesion strength, but also a high current density, we have tried to find out the optimum condition which meets the two requirements at the same time by changing experimental factors such as PEI concentration, thickness of the layer and by mixing some additives into the PEI. The adhesion strength and the electrical current density were investigated by tensile tests and electron only device (EOD) experiments, respectively. The results showed that at higher PEI concentration the adhesion strength showed higher value, but the electrical current through the PEI layer decreased rapidly due to the increased PEI layer thickness. We added Sorbitol and PolyEthyleneGlycohol (PEG) into the 0.1 wt% PEI solution to enhance the adhesion and electrical properties. With the addition of the 0.5 wt% PEG into the 0.1 wt% PEI solution, the device showed an electrical current density of 900 mA/cm² and a good adhesion characteristic also. These data demonstrated the possibility of fabricating all-solution-processed OLEDs using two-substrate bonding technology with the PEI layer as an adhesion layer.

• Composites Research
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• v.25 no.6
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• pp.205-210
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• 2012

The single carbon fiber tensile test was performed with electrical resistance measurement. Tensile property of single carbon fiber which accompanied by the relationship between the electric resistance and the strain was investigated. Since the collected data showed a linear relationship between them, the coefficient of fiber slip ratio (FSR) was obtained by computation. The fragmentation specimen (FS) was tested under tensile loading, and the single carbon fiber broke first due to the stress transferring form matrix to reinforcing fiber. The stress distribution of carbon fiber could be observed via the electrical resistance change. Slipping between carbon fiber and matrix was predicted based on the fragmentation test results, and the FSR was used to evaluate interfacial adhesion comparatively. The large FSR indicated poor interfacial bonding. Work of adhesion between carbon fiber and matrix was measured to verify the FSR method, and two results exhibited a consistent conclusion.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.450-455
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• 1999

Unsaturated diol (UD) was prepared from the esterification of maleic anhydride with diethylene glycol (DEG). Unsaturated polyesters modified with rosin (UPMR) or with rosin maleic anhydride adduct (RMA) from 2-hydroxyethylmethacrylate (HEMA) and rosin (UPMRH) were prepared by the reaction of UD with RMA or RMA-HEMA. After crosslinking of UPMR and UPMRH with styrene and methylmethacrylate (MMA), respectively, solvent resistance, tensile strength, and adhesion property of the resins were measured. UPMR crosslinked with styrene or MMA shows an excellent resistance to water and acid. Solvents resistance and tensile strength of UPMR using styrene as crosslinking agent were increased compared with those of UPMR using MMA as crosslinking agent. UPMRH showed better solvents resistance and tensile strength than UPMR. Adhesion strengths of UPMR crosslinked with styrene and MMA were 1.61 and 3.02 MPa, and those of UPMRH were 2.32 and 3.89 MPa, respectively.

• Journal of Adhesion and Interface
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• v.15 no.3
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• pp.109-115
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• 2014

In this study, we synthesized and identified microcapsule containing isocyanate, and investigated the mechanical and adhesion properties of polyurethane resin by adding microcapsule. We found out that the core material of microcapsule and the component weight fraction of microcapsule from the FT-IR and TGA analysis. From the results of adhesion and mechanical property tests, we confirmed that in case of using microcapsule for adhesive resin composition, adhesion strength, tensile strength and abrasion were improved by cross-linking reaction between urethane and IPDI in microcapsule.

• Journal of the Korean Vacuum Society
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• v.13 no.4
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• pp.175-181
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• 2004

We investigated the stability of the DLC film coated on 304 stainless steel substrate by Radio frequency assisted chemical vapor deposition method. Fracture and spallation behaviour of the coating was observed during micro-tensile test of the fil $m_strate composite. As the tensile deformation progressed, the cracks of the film were observed in the perpendicular direction to the tensile axis. Further deformation resulted in the plastic deformation with $45^{\circ}$ slip bands on the substrate surface. Spallation of the film occurred with the plastic deformation, which was initiated at the cracks of the film and was aligned along the slip directions. We found that both the cracking and the spallation behaviors are strongly dependent on the pre-treatment condition, such as Ar plasma pre-treatment. The spallation of the film was considerably suppressed in an optimized condition of the substrate cleaning by Ar glow discharge. We observed the improved stability with increasing duration of Ar plasma pre-treatment.nt.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.74-80
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• 2021

This study investigated the process quality level of a K5 gas mask, which recently acquired its operational capability, through statistical process analysis for the mass production stages and their lots. The tensile adhesion strength was the only operating requirement in the manufacturing process of the K5 gas mask. For this purpose, the results of tensile adhesion strength between the lens and facial rubber during the initial and second mass production stages were analyzed using conventional statistical and statistical process analysis methods. The conventional statistical results indicated that the second mass production stage was better than the initial mass production stage. In cases of a control chart and process capability of tensile adhesion strength, the process quality level was also improved by following the mass production stages. The improvement was caused by process stabilization and work skill elevation. These results and methods are expected to be conducted and utilized in the third mass production stage. Moreover, quality improvement of K5 gas mask mass production can be achieved using the Lean 6 sigma procedure, MDAIC (Define, Measure, Analyze, Improve, Control).

• Journal of Veterinary Clinics
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• v.26 no.4
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• pp.324-330
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• 2009

This study was performed to determine the effectiveness of poloxamer/sodium alginate mixture(PX/SA) barriers on prevention of post-operative peritoneal adhesion in dogs. Fifteen mongrel dogs were divided into three experimental groups: non-treated group, 2% Sodium Carboxymethylcellulose (SCMC) treated group and PX/SA treated group. In order to induce adhesions, the anti-mesenteric serosa of the ileum was exteriorized and then abraded in a standard manner by scraping with a scalpel blade to create homogeneous petechial hemorrhagic surface over a 1 ${\times}$ 1 cm area. Solution of SCMC was allowed to spread across the intraperitoneal organs through a catheter using a syringe. PX/SA was simply coated over the abraded tissues. On day before and day 1, 4, 7, and 14 after operation, venous blood specimens were collected for measurement of RBC, total WBC and fibrinogen. The adhesions were blindly assessed 3 weeks later by using a computerized tensiometer. The RBC, total WBC and fibrinogen values of three groups showed no statistical significances. The mean tensile strength(gram force, gf) of formed adhesions on day 21 after surgery was 173.05${\pm}$113.48 in the non-treated group, 111.42 ${\pm}$ 38.25 in the SCMC group, and 69.00 ${\pm}$ 45.07 in the PX/SA group. The tensile strength values for adhesion seperation in PX/SA group was lower than those in SCMC group(p < 0.05) and significantly lower than those in the non-treated group(p < 0.05). Our data suggested that PX/SA should be effective on reducing peritoneal adhesion formation in dogs compared with SCMC. PX/SA may be applicable to preventing post-operative intraperitoneal adhesion in dogs.

• Journal of Adhesion and Interface
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• v.10 no.2
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• pp.98-105
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• 2009

Poly(amic acid) was synthesized from the reaction of p-PDA/ODA and PMDA/BPDA and silane oligomer containing epoxy group was also synthesized from the reaction of tetramethylorthosilicate (TMOS) and glycidol. After hybridizing poly (amic acid) and silane oligomer, they were effectively converted into polyimide/silica hybrid films by thermal imidization process. As the silica contents in hybrid films increased, CTE values decreased from 17 ppm/K to 10 ppm/K and the tensile modulus increased, in spite of decreasing tensile strength. In addition, the peel test showed that the adhesion strength of hybrid film was enhanced from $0.43kg_f/cm$ to $1.02kg_f/cm$. Therefore, it could be concluded that the polyimide/silica hybrid film is effective to enhance adhesion strength for FCCL films.