Professor Albert van Reenen

Professor Office Room 2005, Polymer Science Building Tel: +27-21-808 3168 Email

 

Tertiary education

• BSc University of Stellenbosch, 1982
• BSc Hons University of Stellenbosch, 1983
• MSc University of Stellenbosch, 1985
• PhD (Polymer Science), University of Stellenbosch, 1988

Research summary

Research interests are presently focused on polyolefins in general.  This encompasses fractionation and characterization, at a molecular level, of these materials.  The structure-property relationships of these materials are of prime interest.  Additional interests are the solution crystallization studies of the polyolefins and other materials, polymer-natural fibre composites and nanocomposites, and polymer modification and functionalization for application in the biological and biomedical fields.

Research description

Fractionation and characterization of polyolefins

The relationship between material structure and material properties is well understood to be central to all material sciences, not least polymer science. In the case of polymers, the relationship between polymer morphology and polymer properties is therefore of cardinal importance. The only way that we can confidently predict polymer properties and, by extension, design polymers with specific properties is to first understand fully what the effect of molecular makeup has on polymer properties. Thereafter an understanding of how catalyst chemistry affects molecular makeup will allow for the manufacture of “tailored” polymers. The ability to fractionate and characterize polyolefins fully is the first step to understanding the relationship between the composition of the fractions and their role in the macroscopic properties of the polymer.  Central to our research is therefore the ability to fractionate and characterize polyolefins. Many techniques are applied according to published procedures, without fully understanding the effect of varying experimental parameters of these techniques. Some effort in our group has recently gone into the study of these fundamental issues in polymer characterization. The most significant progress recently has been in the use of variable temerpature solid state 13C NMR to study the molecular phase development in solid, commercial polyolefins.

Solution crystallization studies of polymers

With the construction of our own instrument, the method of Solution Crystallization Analysis by Laser Light Scattering (SCALLS) has been developed and applied to (mostly) polyolefins.  The method developed allows us to rapidly evaluate both the solution crystallization and solution melting behaviour of polymers.  This methodology has allowed us to study not only polyolefins, but also biopolymers such as poly(lactic acid).

Other interests

Presently, research directions that involve the production of natural fibre (nano)composites is of on-going interest, as is the development of functionalized materials for biological and biomedical applications.  In the latter case, the development of polymeric sensors is a particularly interesting field.

Publications

B Effah, M Meincken, AJ van Reenen.  Characterisation of the interfacial adhesion of the different components in wood–plastic composites with AFM. Springer Science Reviews 3(2) (2015) 97-111. DOI: 10.1007/s40362-015-0032-8

I Amer, AJ van Reenen, T Mokrani.  Molecular weight and tacticity effect on morphological and mechanical properties of Ziegler-Natta catalyzed isotactic polypropylenes.  Polímeros 25(6) (2015) 556-563.  DOI: 10.1590/0104-1428.2158

AJ van Reenen, L Botha, H Duveskog, P Sinha.  Development of structure-property relationships in commercial heterophasic ethylene propylene copolymers (HEPC).  Feature article (invited).  Macromolecular Reaction Engineering 9 (2015) 9 313–324.  DOI: org/10.1002/mren.201400043

AJ van Reenen, M Swart.  The effect of controlled degradation on the molecular characteristics and properties of heterophasic propylene-ethylene copolymers.  Journal of Applied Polymer Science 132(14) (2015) 41783.  DOI: 10.1002/APP.41783

I Amer, AJ van Reenen, M Brand. Use of a solution crystallization analysis by laser light scattering for studying the solution crystallization of different Ziegler–Natta catalyzed polypropylenes.  Polymer International, 64(4) (2015) 466–476. DOI: 10.1002/pi.4811.

TS Motsoeneng, AJ van Reenen, AS Luyt.  Structure and properties of a β-nucleated polypropylene impact copolymer.  Polymer International 64(2) (2015) 222-228. DOI: 10.1002/pi.4778.

AJ van Reenen, R Neppalli, DD Robertson. Solution crystallization analysis of poly(lactic acid): a facile approach for thermal analysis of polymers in solution.  Polymer Testing 40 (2014) 79-87.  DOI: 10.1016/j.polymertesting.2014.08.015

AJ van Reenen, L Botha, P Sinha, H Duveskog, S Joubert.  Solution and solid state NMR characterization of heterophasic propylene-ethylene copolymers (HEPCs) with increasing ethylene content.  European Polymer Journal 59 (2014) 94-104. DOI: 10.1016/j.eurpolymj.2014.07.010