Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 5968                                                        ISSN: 1017-6020/1993

 

State of Compatibility in Crystalline Polypropylene/ABS

 

Amorphous Terpolymer Thermoplastic Blends

 

Effect of Styrenic Copolymers as Compatibilisers

 

M. Frounchi and R.P. Burford

Department of Polymer Science, The University of New South Wales, Kensington, NSW 2033, Australia

 

ABSTRACT

 

The state of compatibility in isotactic polypropylene and ABS blends is investigated using SEM, DSC, DMA and tensile modulus analysis. Interfacial tension is evaluated in terms of dispersed domain size. Impact behaviour of blends is interpreted on a solubility parameter basis. Styrenic block copolymers are used as compatibilisers. Marginal improvements in mechanical properties of PP‑rich blends were observed, whereas in ABS‑rich blends practically no contribution was detected.


Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 6973                                                        ISSN: 1017-6020/1993

 

Electropolymerization of Thiophenes by Cyclicvoltammetry in

 

Aqueous and Organic Medium: Sweep Rate Influence

 

B. Pourabbas, N. Arsalani and A.A. Entezami

Polymer Lab., College of Chemistry, Tabriz University, Tabriz, I.R. Iran

 

ABSTRACT

 

Conducting polymers can be generated chemically and electrochemically. Electrochemical polymerization is easy to control and gives better results. There are many kinds of monomers that can be converted to conducting polymers including 5‑membered heterocycles such as thiophenes and pyrroles which are interesting because of their suitable properties. Here, we attempt to find more suitable electrochemical polymerization conditions. The method of choice is cyclicvoltammetry and the influence of electropolymerization conditions are studied. Thiophene (T), 3‑methylthiophene (3‑MeT) and 3‑bromothiophene (3‑BrT) are electropolymerized on Pt electrode in nitrobenzene and also perchloric acid (9.1 M). The electroactivity of polymers prepared by different sweeping rates is studied. The optimum sweeping rates found at given temperatures are 20 (mV/s) for all cases except 3‑MeT in acidic medium, which is 10 (mV/s).

 


Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 7479                                                        ISSN: 1017-6020/1993

 

Phase Transfer Catalysis in Polycondensation Processes. IX.

 

 Study on Polyetherification of 3,3‑bis (chloromethyl)

 

Oxetane and Bisphenol A

 

V. Bulacovschi, N. Hurduc, C. Mihailescu, C. Ibanescu and C.I. Simionescu

Department of Macromolecules, Polytechnical Institute of Jassy, Jassy, Romania

 

ABSTRACT

 

The polycondensation of 3,3‑bis (chloromethyl) oxetane (BCMO) with bisphenol A (BPA) under the phase transfer conditions is investigated. Second order, central, composite, rotatable experimental design is used in order to carry out this work and to mark limits of the experimental field for better yields and stable mesophase on a large domain.

 


Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 80 83                                                       ISSN: 1017-6020/1993

 

Exact Determination of the Critical Exponent of the Indefinitely

 

Growing Self‑Avoiding Walk on a Two Dimensional Sierpinski

 

Gasket

 

M.A. Jaffarizadeh and S.K. Seyed‑Yagoobi

Department of Physics, University of Tabriz, Tabriz, I.R. Iran

 

ABSTRACT

 

Using an exact real space renormalization group technique, we show that indefinitely growing self‑avoiding walks on the two dimensional Sierpinski gasket have the value 0.798625 for the critical exponent n.

 


Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 8489                                                        ISSN: 1017-6020/1993

 

Copolymers XIV. Acrylic Copolymers Containing a‑Methyl‑

 

Styrene and Poly(Ethylene Glycol)‑ Dinonyl Phenoxy‑Poly

 

(Ethylene Glycol)‑Phosphite Acrylate

 

M. Nicu, M. Lungu and D. Asandei

Department of Macromolecules, Polytechnic Institute of Jassy, Jassy, Romania

A. Lungu

Department of Physical Chemistry, Polytechnic Institute of Jassy, Jassy, Romania

 

ABSTRACT

 

Acrylonitrile (AN) with a‑methyl styrene (MS) and poly (ethylene glycol)‑dinonyl‑phenoxy‑poly (ethylene glycol)‑phosphite acrylate (AP) terpolymerization is studied in aqueous medium at 60 C with potassium persulfate and sodium metabisulfite (K2S2O8 + Na2S2O5) system as an initiator as well as by the mass procedure at 65 C with AIBN as an initiator. In all cases the terpolymers are formed according to the Alfrey‑Goldfinger terminal model. The reactivity ratios of the MS + AP system are calculated and checked, and the following values found: r2=0.0052 and r3=0.0002. At low conversions, depending on the MS concentration in the substratum, this is consumed and AN + AP copolymers are further formed according to the Mayo‑Lewis terminal model. At high conversions the resulting "terpolymers" consist of an homogeneous mixture of AN + MS + AP terpolymers and AN + AP copolymers.

 


Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 90 97                                                       ISSN: 1017-6020/1993

 

Synthesis of Novel Monomers via Benzyne and

 

Bisbenzyne Intermediates

 

S.E. Mallakpour

Polymer Chemistry Laboratory, College of Chemistry, Isfahan University of Technology, Isfahan, 84156, I.R. Iran

 

ABSTRACT

 

2‑Oxo‑1,3‑bis(methoxy carbonyl)‑2‑H‑cyclopenta [i] acenaphthylene is prepared from base ‑ catalyzed condensation of dimethyl‑1,3‑acetone dicarboxylate with acenaphthenequinone. Benzyne generated from anthranilic acid is trapped with this cyclone and 7,12‑dimethyl carboxylate benzo [k] fluoranthene as a new monomer is obtained in quantitative yield. Bisbenzyne from aprotic diazotization of 3,3'‑dicarboxy-4,4'‑diaminobiphenyl is also trapped with this cyclone and leads to the formation of tetra functional methyl carboxylate of bisbenzo [k] fluoranthene derivative.

 


Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 98 102                                                     ISSN: 1017-6020/1993

 

Determination of the Molecular Weight of Polyacrylamide

 

Fractions by Osmometry

 

M.R. Saboktakin, H. Namazi and A.A. Entezami

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

 

ABSTRACT

 

Vinylic compounds, such as acrylamide, in aqueous solutions, are reacted with some organic compounds and inorganic reducing agents to give polymer solutions in water. The polymerization of acrylamide with "hydroxylamine sulfonic acid‑iron (II) sulfate heptahydrate" redox system (pH=22.5) is carried out in aqueous medium at 30 and 40 C. The obtained polyacrylamide is fractionated by the triangular fractionation method using methanol as a non‑solvent. Molecular weights of the fractions are determined by cryoscopic osmometry and viscometry. Then, integral and differential distribution curves of samples are plotted using the fractionation data.

 


Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 103105                                                    ISSN: 1017-6020/1993

 

Analysis of PVC and Separation of Plasticizer with

 

Mixed Solvents

 

M.T. Kossarneshan

Chemical Engineering Department, University of Science and Technology, I.R. Iran

 

ABSTRACT

 

The mixed solvents technique is a suitable way to study components of polyvinyl chloride (PVC) materials [1]. In this study, cyclohexanone or N,N‑dimethylformamide (DMF) is used as a basic solvent to completely dissolve polymeric materials of PVC. The separation of dioctylphthalate (DOP) which is used as a plasticizer is obtained by the pretreatment method of the analysis of PVC compound. IR Spectroscopy is used to characterize the plasticizer. It is shown that a perfect separation is achieved by changing the ratio of the mixed solvents.

 


Iranian Journal of Polymer Science and Technology / Volume 2 Number 2 (1993) 106112                                                    ISSN: 1017-6020/1993

 

Direct Oxidative Methane Conversion to Ethylene Using

 

Perovskite Catalyst

 

R.D. Golpasha, D. Karami, R. Ahmadi and E. Bagherzadeh

N.I.O.C., Research Institute of Petroleum Industry, Tehran, I.R. Iran

 

ABSTRACT

 

The catalytic oxidative coupling reaction of methane over CaTiO3 perovskite prepared by the modified ceramic method is carried out and is found to be an active and selective catalyst to higher hydrocarbons like the other perovskites. A C2 yield of 13% is obtained over this catalyst at 830 C. There is no appreciable change in either the methane conversion or C2 yield during 200 hours of reaction. Promotion with Na4P2O7 is not found to improve considerably the performance of the catalyst. An X‑ray analysis shows that three oxides phases (CaTiO3, CaO, MgO) are present in solid solution after calcination at 850 C with the higher amount of CaTiO3 phase. With consideration of reactor experiments and obtaining the optimum conditions required to achieve good activity, from a mechanistic point of view it is believed that oxygen charge deficient O- being generated by transforming oxygen adsorbed on surfacial defects and dissolved into bulk vacancies is responsible for activating methane (the activating site). Oxygen adsorbed generates the oxidizing sites for suppressing the activated methane. The strict conditions are supposed to be due to difficulty in generating and regenerating the activating sites in the lattice.