Iranian Polymer Journal / Volume 6 Number 1 (1997) 5–17                                                        ISSN: 1026-1265/1997

 

 

Study of Polymerization Mechanism and Kinetics of DGEBA with

 

BF3‑amine Complexes Using FT‑IR and Dynamic DSC

 

M. Ghaemy and M.H. Khandani

Department of Chemistry, University of Mazandaran, Babolsar, I.R. Iran

 

ABSTRACT

 

The diglycidyl ether of bisphenol A and boron trifluoride‑diethylamine, monoallylamine and piperidine complexes are used in a model system to investigate the cure reaction which occur during polymerization. Experiments using FT‑IR at different temperatures show that boron trifluoride‑amine complexes break down rapidly to tetrafluoroboric acid at 100 ºC and above. Tetrafluoroboric acid forms complexes with epoxy groups, producing an activated monomer that reacts with epoxy in an etherification reaction. Dynamic DSC thermograms also show a small exotherm peak due to complex formation before the large exotherm peak of etherification reaction. A phenomenological approach is used to characterize the cure kinetics. Kinetic analysis, using integral procedure on dynamic data, indicates that the cure reaction data of diglycidyl ether of bisphenol A with boron trifluorideamine complexes can be described well with the homogeneous first‑order reaction model. The activation energies are found to be in the range of 90.85 kJ/mol for boron trifluoride‑diethylamine; 96.88 kJ/mol for boron trifluoride-monoallylamine; and 94.45 kJ/mol for boron trifluoride‑piperidine complexes.

 


Iranian Polymer Journal / Volume 6 Number 1 (1997) 19–26                                                      ISSN: 1026-1265/1997

 

 

Starved Feeding for Improving the Mechanical Properties of

 

Styrene‑Butadiene Rubber Vulcanizates

 

P.J. Joseph Francis, R. Joseph and K.E. George

Department of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Kochi-682 022, India

 

ABSTRACT

 

Gum and filled compounds styrene‑butadiene rubber are extruded through a laboratory extruder by varying the feeding rate at different temperatures and screw speed (rpm). The extruded compounds are vulcanized up‑to their optimum cure times and the mechanical properties of the vulcanizates are determined. From the properties data obtained it is concluded that there is a specific feeding rate within the starved fed region, which results in maximum improved mechanical properties. The enhancement in properties is found to be due to better thermal and shear homogeneity.

 


Iranian Polymer Journal / Volume 6 Number 1 (1997) 27–34                                                      ISSN: 1026-1265/1997

 

 

Immobilization of Amino Functionalized Polyacrylamide on Silica

 

Surface as Chelating Agent for Liquid Chromatography

 

Y. Mansoori and A.A. Entezami

Polymer Laboratory, Faculty of Chemistry, University of Tabriz, Tabriz, I.R. Iran

 

ABSTRACT

 

Amino functionalized polyacrylamide can be used as a polymeric chelating agent. In this work silica has been used as an inorganic support for organic polymer. Silica has been silylated with vinyltrichlorosilane, and then it is polymerized with acrylamide in the presence of benzoyl peroxide as an initiator. Polyacrylamide supported on silica has been transamidated with ethylenediamine to give poly(N‑2‑aminoethylacrylamide) immobilized on silica. This modified silica has been characterized with FT‑IR, DSC, and elemental analysis and it is complexed with Cu(ll), Co(ll), Fe(III), Ni(ll). Metal uptake capacity of this modified silica towards metal ions, especially Cu(ll) cation, is several times greater than other silica‑bound complexing agents such as silica modified 8‑hydroxyquinoline and organic amines.

 


Iranian Polymer Journal / Volume 6 Number 1 (1997) 35–41                                                      ISSN: 1026-1265/1997

 

 

Application of Conducting Polymer Membranes Part 1:

 

Separation of Nitric and Phosphoric Acids

 

A. Mirmohseni and A. Saéedi

Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, I.R. Iran

 

ABSTRACT

 

The development of membrane systems that are dynamic in structure can attribute a new dimension in separation technology. The paper presents separation of two inorganic acids (HNO3/H3PO4) using conducting polyaniline membrane. The inherent dynamic and controllable properties of the conducting polymers are used to exploit a new method of separation. In this method the transport of each species can be switched on/off during separation. The acids (HNO3/H3PO4) are successfully separated using the polyaniline membrane.

 


Iranian Polymer Journal / Volume 6 Number 1 (1997) 43–51                                                      ISSN: 1026-1265/1997

 

 

Modification of a Composite Membrane for Redox

 

Flow Battery Applications

 

T. Mohammadi and V. Haddadi‑Asl

School of Chemical Engineering and Industrial Chemistry, The University of New South Wales, Sydney, Australia

 

ABSTRACT

 

A composite membrane from a single sheet of Daramic, a microporous separator, is prepared by incorporation of an anion exchange resin, Amberlite CG 400, and further cross‑linking with divinylbenzene [1]. Further modification and characterization of the composite membrane are now described. A detailed FESEM, TGA, FT‑IR and 13C NMR analyses of the composite membrane have been carried out. The ion exchange capacity of the composite membrane has been also evaluated. Formation of thin layer of polydivinylbenzene after cross‑linking is confirmed by morphological studies. None of the experiments show incorporation of the ion exchange resin into the composite membrane.

 


Iranian Polymer Journal / Volume 6 Number 1 (1997) 53–61                                                      ISSN: 1026-1265/1997

 

 

Application of Artificial Intelligence Methods in Conducting

 

Polymer Based Sensors

 

A. Talaie and J. Romagnoli

ICI Laboratory for Process Systems Engineering, Department of Chemical Engineering

The University of Sydney, Sydney 2006, NSW, Australia

 

ABSTRACT

 

Conducting polymers such as polypyrrole and polyaniline represent a new class of organic polymers that are capable of molecular interactions and being able to interact, chemically or electrochemically, with the species of interest for detection. Although these conductive materials have unique properties they have their specific problems with respect to their reproducibility and reusability. Problems exist due to the dynamic nature of these polymers thereby mitigating against their successful application as novel sensors. This has also hindered the production of analytically useful, sensitive, and reversible signals by using these polymers. This paper has sought to examine these problems through the introduction of new series of integrated artificial intelligence/conducting polymer based sensor. In this type of sensors analytical responses, which look irreversible and non-producible, are combined by an artificial intelligence trained computer by which reproducible output, based on the created model and pattern by the computerized system, can be predicted. This paper demonstrates and compares the applications of artificial neural networks, and fuzzy methods in the realm of modelling and pattern recognition. It has been found that the neural network approach has more flexibility in modelling than the fuzzy approach.

 


Iranian Polymer Journal / Volume 6 Number 1 (1997) 63–71                                                      ISSN: 1026-1265/1997

 

 

Synthesis and Characterization of Acrylic Monomer and its

 

Polymer with Pendant Acetaminophen and Investigation of

 

Polymer Ability for Drug Release

 

Z. Momenkhany and S.M. Taghizadeh

Polymer Research Center of Iran, Tehran, I.R. Iran

 

ABSTRACT

 

Nowadays, the increasing consumption of drugs have strongly propounded problems such as drug accessability, on‑time usage with exact dose, daily multi-usage, and the side effects being the most serious of all. The scientific community has always been searching ways for reduction of these difficulties. Drug controlled release system is one of the ways which has attracted considerable attention in recent years, and it is defined as the release of drug in specified parts of the body with a required dose and desirable specific rate which itself consists of various techniques. In this research the method employed is the chemically controlled release with 4-­hydroxyphenyl acetamide (acetaminophen) as the drug. Thus, acetaminophen and acryloyl chloride are converted to an acrylic monomer, then the obtained monomer is polymerized, and finally the drug release ability of the polymers is tested in buffer solution. These tests show that the polymers are able to release drug but with insignificant amount and this as a preliminary step is a good sign and satisfactory.