Iranian Polymer Journal / Volume 9 Number 1 (2000)                          ISSN: 1026-1265/2000

 

Towards a Conducting Polymer-based Electronic Nose

 

and Electronic Tongue

 

A. Talaie1,4(*), J.Y. Lee2,  H. Eisazadeh3, K. Adachi1, J.A. Romagnoli4  and T. Taguchi1

(1) Department of Organic Materials, Osaka National Research Institute,  Midorigaoka, Ikeda, Osaka 563, Japan

(2) Department of Applied Science, The University of New South Wales, Kensington, NSW 2033, Australia

(3) Department of Chemical Engineering, University of Mazandaran, PO Box 484, I.R. Iran

(4) Chemical Engineering Department, The University of Sydney, NSW 2006, Australia

 

Received 17 August 1998; accepted 25 September 2020

 

ABSTRACT

 

An integrated system has been designed for detection of gas, volatile liquid and liquids based on the concept of an electronic nose and an electronic tongue. The detection mechanism relies on the changes in electrical resistance that occurs when an array of microelectrodes, coated with conducting polymers, is exposed to different samples. The data collected from such resistance changes has been processed by an artificial intelligence trained computer in conjunction with pattern recognition data analysis to identify and quantify the chemicals of interests. Detection of pH and sodium chloride was considered as case studies for the electronic nose and tongue applications respectively. This integrated artificial intelligence/electronic nose and tongue can be further developed to detect colour (electronic eye) for display device applications.

 

Key Words: electronic nose, electronic tongue, computer modeling, conducting polymer

 

 

Iranian Polymer Journal / Volume 9 Number 1 (2000)                          ISSN: 1026-1265/2000

 

Drawing Temperature and Mechanical Properties

 

of High‑density Polyethylene Drawn Tapes

 

S.K. Rana

Centre for Polymer Science and Engineering, Indian Institute of Technology Delhi

New Delhi‑110016, India

 

Received 16 August 1999; accepted 12 February 2021

 

ABSTRACT

 

The effect of drawing temperature on the mechanical properties of high‑ density polyethylene (HDPE) tape is explored through scanning electron microscope and differential scanning calorimeter using etching as a tool for investigation. The HDPE tape was made by a hot melt extruder fitted with a bottom fed die and was drawn in (i.e., oriented), on‑line on a hot plate maintained at constant temperature. It is shown that the drawing temperature of 82 ºC produces a tape with better mechanical properties with a draw ratio of 8.4 than the tapes drawn at 62, 72 and 92 ºC to the same draw ratio. Thin and notch free fibrils and those containing long chain crystallites are attributed for this superior behaviour in mechanical properties. Taut heat setting shows that out of varied range of crystallites produced during drawing, short folded chain and long folded chain crystallites are stable and the long folded chain crystallites are responsible for making tapes mechanically stronger.

 

Key Words: drawing, morphology, tape, crystallization, melting

 

 

Iranian Polymer Journal / Volume 9 Number 1 (2000)                          ISSN: 1026-1265/2000

 

Poly(N‑vinyl‑2‑pyrrolidone)‑polyacrylamide

 

Hydrogels as Extraction Solvents

 

S.K. Bajpai

Department of Chemistry, Goverment Autonomous Science College, Jabalpur‑ 482 001 (M.P.), India

 

Received 23 February 1999; accepted 8 December 2020

 

ABSTRACT

 

Polymeric hydrogels, composed of poly(N‑vinyl‑2‑pyrrolidone) and cross-linked polyacrylamide have been synthesized for the purpose of concentrating protein solutions by excluding water from them. The hydrogles showed pH‑independent swelling behaviour, which was attributed to the non‑ionic nature of polymers present in the gel. The hydrogels proved to be an efficient device to extract water from the protein solutions. The extraction efficiency of the hydrogels was found to increase with the increase in cross-linking ratio. Similarly, the gel efficiency has been found to decrease with the increase in concentration of protein solutions. Hence, gels have proved to be an effective device to exclude water from dilute protein solutions. The swollen gels returned to their original shape, when dried in a vacuum oven at 40 °C for 48 h. The de‑swollen gels were re-used for the extraction purpose. In order to reflect the quantitative aspect of swelling behaviour, various parameters such as swelling exponent n, diffusion coefficient D, have also been evaluated. The gels with cross-linking ratio 1.5 (in mole%) were found to follow non‑fickian swelling mechanism, while gels with cross-linking ratio 3.0 and 4.5 (in mole%) showed Fickian swelling behoviour.

 

Key Words: poly(N‑vinyl‑2‑pyrrolidone), polyacrylamide, extraction solvent, cross-linking ratio, gel efficiency

 

Iranian Polymer Journal / Volume 9 Number 1 (2000)                          ISSN: 1026-1265/2000

 

Obtaining of Fire‑retardant Polyamide 6 Grades without

 

Halogens for Injection Moulding

 

Mihai Rusu1(*), Constanta Ibanescu1, Marius Murariu2, Lilia Harabagiu2, Alexandrina Bordeianu2

(1) Technical University “Gh. Asachi” Iasi, Faculty of Industrial Chemistry, Macromolecular Department

Bd. Copou Nr. 11A, 6600-Iasi, Romania

(2) ICEFS S.A. Savinesti, 5612 Savinesti, Uzinei Street Nr. 1, Neamt, Romania

 

Received 2 January 1997; accepted 8 February 2021

 

ABSTRACT

 

In a great number of countries, restrictions have been imposed in using materials with high flammability and the fire retardant plastics are preferred. The fire retardant grades of polyamides represent an outstanding category in the group of this kind of polymers for injection moulding. We obtained polyamidic composites with reduced flammability by compounding polyamide 6 with melamine and concluded that introduction of 15–20 % melamine in PA 6 is an interesting possibility of obtaining fire retardant composites without halogens. Having good mechanical and flammability characteristics, these composites may be used for obtaining items for electronics and automotive industry.

 

Key Words: fire‑retardants, polyamide, melamine, composites, injection moulding

 

 

Iranian Polymer Journal / Volume 9 Number 1 (2000)                          ISSN: 1026-1265/2000

 

Chemical Recycling of Polyethylene Terephthalate

 

Mahmood Mehrabzadeh1(*), Sharareh T. Shodjaei2 and Morteza Khosravi2

(1) Iran Polymer Institute, P.O. Box: 14965/115, Tehran, I.R. Iran

(2) Islamic Azad University, North Tehran Branch, P.O. Box: 197351/1486, Tehran, I.R. Iran

 

Received 13 December 1999; accepted 31 January 2021 

 

ABSTRACT

 

Polyethylene terephthalate (PET) is one of the most important and commercial thermoplastics polyesters which has been in the market since 1977 and it has vastly been used both in industry and household. Through chemical recycling, plastics can be converted into their primary components for use in other chemical processes under especial conditions. Polyethylene terephthalate is a thermoplastic, therefore, recycling by chemical method which converts it into primary components can be achieved. In this study the optimal routes of the existing chemical methods have been chosen. For chemical recycling, acidic hydrolysis is used and PET is converted to terephthalic acid (TPA) and ethylene glycol (EG). Effective factors in the decomposition and the yield such as acid concentration, time, temperature and PET particle size were investigated. Characterization of the products is carried out by FTIR, and the effect of reaction time on PET particles is evaluated by scanning electron microscopy.

 

Key Words: chemical recycling, polyethylene terephthalate, hydrolysis, terephthalic acid, ethylene glycol

 

 

Iranian Polymer Journal / Volume 9 Number 1 (2000)                          ISSN: 1026-1265/2000

 

Synthesis of Novel Optically Active Poly(amide-imide)s with

 

Benzophenone and L-Alanine Moieties

 

Shadpour E. Mallakpour*, Hossein A. Dabbagh and Khalil Faghihi

Organic Polymer Chemistry Research Laboratory, College of Chemistry, Isfahan University of Technology

Isfahan, 84156, I.R. Iran

 

Received 15 June 1999; accepted 19 October 2020

 

ABSTRACT

 

3,3’,4,4’-Benzophenonetetracarboxylic  dianhydride  (4,4’-carbonyldiphthalic anhydride) 1 was reacted with L-alanine 2 in a mixture of acetic acid and pyridine (3:2) at room temperature, then was refluxed at 90–100 ºC and the resulting imide-acid  4  was obtained in quantitative yield. The compound  4  was converted to the diacid chloride  5  by reaction with thionyl chloride. The polymerization reaction of the imide-acid chloride  5  with benzidine  6a,  4,4’-diaminodiphenyl methane  6b,  1,5-diaminoanthraquinone 6c, 2,6- diamino pyridine  6d  and 4,4’-sulfonyl dianiline  6e  was carried out in DMAc solution in the presence of pyridine. The resulting poly(amide-imide)s were obtained in high yield and are optically active and thermally stable. All of the above compounds were fully characterized by IR spectroscopy, elemental analyses and specific rotation. Some structural characterization and physical properties of this optically active poly(amide- imide)s are reported.

 

Key Words: poly(amide-imide)s, L-alanine, optically active polymers, polycondensation reaction, benzophenone group

 

 

Iranian Polymer Journal / Volume 9 Number 1 (2000)                          ISSN: 1026-1265/2000

 

Conductivity of Textile Fibers Treated with Aniline

 

Mehdi Nouri1(*), Mohammad Haghighat Kish1, Ali A. Entezami2 and Mohammad Edrisi1

(1) Textile Engineering Department, Amir Kabir University of Technology, Tehran, I.R. Iran

(2) Department of Chemistry, Tabriz University, Tabriz, I.R. Iran

 

Received 25 September 1999; accepted 8 February 2021

 

ABSTRACT

 

Various textile fibers in yarn forms were treated with aniline at different oxidative polymerization conditions to improve their electrical conductivities. In addition to the measurement of the electrical resistance, surface texture and fiber cross-sections were examined by an optical and a scanning electron microscope. Attenuated total reflection infra-red spectroscopy was used to detect the formation of polyaniline on the surface of fibers. An attempt was made to correlate the perceived colour of the treated samples via visible light reflection spectroscopy with electrical resistance. At proper condition of treatment, polyaniline formed on the surface of fibers improve the yarns conductivity. The decreases of electrical resistance in nylon, cotton and acrylics were found to be more than polyester and wool yarns. The changes in the mechanical properties of yarns after treatment were insignificant. The stability of different coating processes of polyaniline on the surface of cotton and acrylic yarns were compared. It goes further to explain the results based on the pertinent literature.

 

Key Words: fiber yarns, coating, polyaniline, electrical resistance, conductivity

 

 

Iranian Polymer Journal / Volume 9 Number 1 (2000)                          ISSN: 1026-1265/2000

 

Synthesis and Properties of g(Co‑ 60) Cured Acrylated

 

Urethane Coating

 

 

Akbar Shojaei1, Farah Khoylou2 and Faramarz Afshar Taromi1(*)

(1) Polymer Engineering Department, Amir Kabir University of Technology, P.O. Box: 15875‑4413, Tehran, I.R. Iran

(2) Gamma Irradiation Center, Atomic Energy Organization of Iran, P.O. Box: 11365-8486, Tehran, I.R. Iran

 

Received 5 May 1999; accepted 25 December 2020

 

 

ABSTRACT

 

In this paper, synthesis method of acrylated urethane based on polyethylene glycol and toluene di‑isocyanate as a mixture of two isomers (2,4 and 2,6) has been investigated by application of IR spectra and GPC technique. In this method, reaction schemes were controlled by surveying the –NCO– and –OH absorption peak elimination and –NH– absorption peak formation in IR spectra during the reaction. The mixture of the two isomers leads acrylated urethane resins to contain three oligomers (II, III and IV) in the final product. The study of physical and mechanical properties of g-cured resin showed that hardness and impact resistance vary with increase in dose; meanwhile these quantities indicate a little variation after 60 kGy. This could be due to increasing of cross-link density. Also, addition of reactive monomers to the resin showed that increase in double bonds density in the resin system at a given dose, caused an increase in hardness and a decrease in impact resistance. By addition of a rutile type titanium dioxide as pigment, the hardness of film increases, but the variation of hardness‑dose curve in both unpigmented and pigmented film is the same.

 

Key Words: acrylated urethane, gamma-cured resin, hardness, reactive diluent, pigmented coating