• Polymer(Korea)
• /
• v.31 no.4
• /
• pp.349-355
• /
• 2007

Poly(N-isopropylacrylamide-co-acrylonitrile) [P(NIPAAm-co-AN)] copolymers with AN content of up to 10 mol% and their hydrogels were synthesized using water as a reaction medium, and the effects of AN unit incorporation on the critical gel transition temperature(CGTT) and swelling behaviors of the hydrogels were investigated. The CGTT of the copolymer hydrogel was $30{\sim}32\;^{\circ}C$, decreasing with increasing AN content. Below CGTT, swelling rate and equilibrium swelling ratio of the copolymer hydrogel decreased with increasing AN content. On the other hand, it exhibited faster deswelling and lower equilibrium deswelling ratio with increasing AN content above CGTT.

• Fibers and Polymers
• /
• v.7 no.1
• /
• pp.36-41
• /
• 2006

PVC and SAN are often mixed to compensate for the disadvantages of each polymer. Miscibility and thermal stability of PVC/SAN blend were investigated in this study by blending SAN polymer having 20, 24, 28, 32 % of acrylonitrile contents. Two polymers were mixed using a melt blending method with a single screw extruder. DSC thermogram was used to evaluate miscibility of the two polymers. SAN having 24 % of acrylonitrile showed the best miscibility with PVC. In order to evaluate degradation behavior, blended polymer was heat treated in DSC furnace and glass transition temperature was measured consecutively. Glass transition temperature increased continuously with annealing time due to degradation and cross-linking of polymer chains. Melt index of blended polymer was always higher than that of PVC.

• Macromolecular Research
• /
• v.9 no.1
• /
• pp.30-36
• /
• 2001

Polybutadiene latex grafted (g-PB) in g-PB/SAN blends, i.e., acrylonitrile-butadiene-styrene terpolymer (ABS) were partially replaced by acrylonitrile-butadiene copolymer (NBR) with various acrylonitrile (AN) contents. Changes in morphology, physical and rheological properties were examined. The dispersed size of NBR was decreased as the miscibility with matrix SAM, was increased by increasing AN content in NBR upto 50 wt%. Impact strength was enhanced about two-fold due to the NBR dispersed with a slight larger size than the original g-PB. Gloss was effectively reduced as the particle size of NBR was increased. Tensile yield strength was decreased, and elongation at break or yield behavior at low shear rate were increased as g-PB was partially replaced by NBR having AN content less that 40 wt%.

• Elastomers and Composites
• /
• v.35 no.3
• /
• pp.188-195
• /
• 2000

The conducting composites were prepared by emulsion polymerization with poly (acrylonitrile-co-butadiene) (NBR) as a matrix and polypyrrole (PPY) as a conducting polymer. Among several surfactants, the electrical conductivity of the composite which was polymerized by dodecyl sodium sulfate (DSS) was the best. The film of composite was prepared by compression molding. The electrical conductivity was measured by 4 probes method as a function of PPY and temperature. When the content of PPY was 25 wt%, the electrical conductivity of composite was increased up to 1.17 S/cm. The percolation threshold showed at the vicinity of 15 wt% PPY content.

• Korea-Australia Rheology Journal
• /
• v.12 no.2
• /
• pp.135-141
• /
• 2000

The linear viscoelastic behavior of acrylonitrile-butadiene-styrene (ABS) polymers with different rubber content has been investigated in the frame of a linear viscoelastic model, which takes into account the inter-connectivity of the dispersed rubber particles. The model developed in our previous work has been shown to properly predict the low frequency plateau for the storage modulus, which is generally observed in polymer blends containing core-shell-type impact modifiers. In the present study, further experiments have been carried out on ABS polymers with different rubber content to verify the validity of our linear viscoelastic model. It has been found that our model describes quite properly the rheological behavior of ABS polymers with different rubber content, especially at low frequencies. The experimental data confirm that our model describes the rheological properties of rubber-modified thermoplastic polymers with strong adhesion at the particle/matrix interface more accurately than the Palierne model.

• Polymer(Korea)
• /
• v.31 no.1
• /
• pp.8-13
• /
• 2007

To overcome drawbacks of the nylon 6/poly (acrylonitrile-co-butadiene-co-styrene) (ABS) blend, nylon 6 blend with poly (acrylonitrile - co-styrene - co-acrylic rubber) (ASA) which containing poly (butyl acrylate) as a rubber phase in substitute of poly (butadiene) in ABS, was examined. Poly (styrene-co-maleic anhydride) (SMA) containing 25 wt% of maleic anhydride (MA) or poly (styrene- co-acrylo-nitrile-co-maleic anhydride) (SANMA) containing less than 3 wt% MA was used as a compatibilizer to fabricate blends having high impact strength. Changes in the mechanical properties of nylon 6/ASA blend with compatibilizer content were similar with those of nylon 6/ABS blend. Blends haying high impact strength was produced when blends contained more than about 20 wt% rubber. Blends containing SAM or SANMA as a compatibilizer were stayed in a injection molding machine at the molding temperature and afterwards specimens for the examination of the impact strength was prepared. Impact strength of blends containing SMA was decreased with retention time, while that of blends containing SANMA was not changed with retention time.

• Journal of Sericultural and Entomological Science
• /
• v.20 no.2
• /
• pp.40-44
• /
• 1978

Cerium (IV) ion-initiated graft copolymerizations of acrylonitrile to raw silk were investigated in an effort to carry out sericine-fixation. The change in ceric ammonium nitrate concentration exhibited a maximum in percentage of grafting at 0.003M. Also observed was that the change in nitric acid content in reaction media gave a maximum in percentage of grafting at 0.1M. Percentage of grafting was increased generally with increase in acrylonitrile concentration, reaction time and reaction temperature. Raw silk sericin grafted with acrylonitrile was not de gummed by boiling off test and optimum graft percentage was considered at 20%.

• Journal of the Korean Applied Science and Technology
• /
• v.19 no.1
• /
• pp.33-42
• /
• 2002

Copolymerization of ${\alpha}$-Methylstyrene(AMS) with Acrylonitrile(AN) was carried out with benzoylperoxide(BPO) as an initiator in toluene at $80^{\circ}C$ in a continuous stirred tank reactor. Reaction volume and residence time were 0.6 liters and 3 hours, respectively. The monomer reactivity ratios, $r_{AMS}$ and $r_{AN}$ determined by both the Kele$T{\"{u}}d\"{o}s$ method and the Fineman-Ross method were $r_{AMS}$=0.16(0.14), $r_{AN}$=0.04(0.06). The cross-termination factor ${\Phi}$ of the copolymer over the entire AMS composition ranged from 0.75 to 0.92. The ${\Phi}$ factors of poly(AMS-co-AN) were increased with increasing AMS content. The simulated conversions and copolymerization rates were compared with the experimental results. It was observed that the average time to reach dynamic steady-state was three times the residence time.

• Macromolecular Research
• /
• v.17 no.6
• /
• pp.417-423
• /
• 2009

The effects of maleic anhydride-grafted polypropylene (PP-g-MAH) addition on polypropylene (PP) and poly(acrylonitrile-butadiene-styrene) (ABS) blends were studied. Blends of PP/ABS (70/30, wt%) with PP-g-MAH were prepared by a twin-screw extruder. From the results of mechanical testing, the impact, tensile and flexural strengths of the blends were maximized at a PP-g-MAH content 3 phr. The increased mechanical strength of the blends with the PP-g-MAH addition was attributed to the compatibilizing effect of the PP and ABS blends. In the morphological studies, the droplet size of ABS was minimized (6.6 ${\mu}m$) at a PP-g-MAH content of 3 phr. From the rheological examination, the complex viscosity was maximized at a PP-g-MAH content of 3 phr. These mechanical, morphological and rheological results indicated that the compatibility of the PP/ABS (70/30) blends is increased with PP-g-MAH addition to an optimum blend at a PP-g-MAH content of 3 phr.

• Elastomers and Composites
• /
• v.36 no.2
• /
• pp.111-120
• /
• 2001

Mechanical properties and their adhesion behavior with zinc- and brass-plated steel cords of natural rubber/acrylonitrile-butadiene blend compounds were investigated as a function of blend ratio. The Mooney viscosity and stress relaxation time were found to be lowered with increasing NBR content. Tensile modulus generally increased with increasing NBR content. Tensile stress at break stayed constant up to about 40 phr and showed minimum at $50{\sim}60 phr$, and thereafter increased with increasing NBR content. Strain at break decreased linearly below 50 phr, and above the level it showed nearly constant value. Based on the abrupt drops in elastic modulus and tan ${\delta}$ peak, the glass transition temperature of NR and NBR were found to be -55 and $-10^{\circ}C$, respectively. In the case of NR/NBR blend compounds, two distinct transition points were observed and each transition position was not affected by NBR level indicating an incompatible nature of NR/NBR blend system. The pullout force and rubber coverage decreased to the level of about 40% to that of pure m compound, when the 50 phr of NR was replaced by NBR. However, the pure NBR compound showed the comparable adhesion performance with NR(${\sim}90%$). The sulfur concentration was found to become lower with the increased NBR content at the adhesion interface based on the Auger spectrometer results, representing a lack of adhesion layer formation, and this was explained for a possible cause of low adhesion performance with adding NBR.