Goikoetxea M.,Institute for Polymer Materials |
Reyes Y.,Institute for Polymer Materials |
De Las Heras Alarcon C.M.,University of Surrey |
Minari R.J.,Institute for Polymer Materials |
And 5 more authors.
Polymer | Year: 2012
Films cast from multiphase polymer particles have the potential to combine the properties of their components synergistically. The properties of the film depend on the hybrid polymer architecture and the film morphology. However, how the polymer microstructure and particle morphology are transformed during film formation to determine the film morphology is not well understood. Here, using waterborne alkyd-acrylic nanocomposite particles in a case study, it was found that phase migration leading to the formation of aggregates occurred during film formation. A coarse-grained Monte Carlo model was developed to account for the effects of polymer microstructure and particle morphology on the morphology of the film. The model was validated by comparing its predictions with the observed effects, and then used to explore combinations of polymer microstructure and particle morphology not attainable with the system used as a case study. Significantly, the compatibility of the phases was found to have a greater influence than the morphology of the particles in determining the film structure. © 2012 Elsevier Ltd. All rights reserved.
Nase M.,Hof University of Applied Sciences |
Grossmann L.,Martin Luther University of Halle Wittenberg |
Rennert M.,Institute for Polymer Materials |
Langer B.,Polymer Service GmbH Merseburg |
Grellmann W.,Martin Luther University of Halle Wittenberg
Journal of Adhesion Science and Technology | Year: 2014
The investigated peel system in this study consists of a polyolefine-based, coextruded, three-layer film having ethylene-vinyl acetate (EVAc) copolymer at the interface, heat sealed against a biaxial-oriented polyethylene terephthalate film. This system can primarily be found in the packaging industry offering a residue-free and non-destructive peel behavior. The peel force required to separate the joint depends on the mass fraction of vinyl acetate (VAc) in the EVAc copolymer, the processing conditions in the blowing process of the PE/PEVAc film, and on the sealing parameters. In dependence on the processing conditions and sealing parameters, the standard peel system with EVAc copolymer containing 18 wt.% VAc was investigated. The processing parameters were varied among the processing line of the blown film and their influence on the peel properties were studied. As processing parameters the screw speed within the extruder and the resulting layer thickness, the cooling behavior of the film bubble and the blow-up ratio (BUR) of the film bubble were investigated. The effect of pretreatment conditions was also investigated. The investigations revealed a significant dependence of the peel force on the pretreatment conditions. Processing conditions and the VAc content have a minor impact on the peel properties. © 2014 © 2014 Taylor & Francis.
Daniloska V.,University of Macedonia |
Blazevska-Gilev J.,University of Macedonia |
Dimova V.,University of Macedonia |
Fajgar R.,Czech Institute of Chemical Process Fundamentals |
And 2 more authors.
Applied Surface Science | Year: 2010
The development of different techniques for surface modification of polymers becomes popular in a last decade. These techniques preserve useful bulk polymer properties unchanged, while the activation of the polymer surface offers more possibilities for polymer applications. In this work, a new, one-step method for bio-activation of HDPE (high density polyethylene) surface by UV irradiation is presented. HDPE films coupled with selected active compound and a photoinitiator was treated by UV lamp, emitting light at 254 nm. For surface functionalization of HDPE films, the following compounds were employed: 2-aminopyridine (AP), N 1-(2-pyridylaminomethyl)-1,2,4-triazole (TA) and benzocaine (BC). The influence of irradiation time on the extent of surface changes was investigated. The modified polymer surfaces were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, scanning electron microscopy (SEM) and contact angle measurements, demonstrating successful functionalization of HDPE surface. © 2009 Elsevier B.V. All rights reserved.
Mariz I.d.F.A.,Institute for Polymer Materials |
Millichamp I.S.,Akzo Nobel |
de la Cal J.C.,Institute for Polymer Materials |
Leiza J.R.,Institute for Polymer Materials
Progress in Organic Coatings | Year: 2010
The performance of water-borne paints formulated with five different high solids content acrylic (MMA/BA/MAA) latexes was investigated. These latexes had different particle size distributions (unimodal at 61 wt% and bimodal with the large mode below or above 350 nm at 65 wt% solids), different types of surfactant and in one case the carboxylic monomer was omitted. The results showed that both the particle size distribution of the latex and the paint thickening mechanism were found to be important contributors to wet paint viscosity and dry film properties. It was found that the water-borne paints formulated with the bimodal latex with particle sizes below 350 nm provided the best application properties in terms of drying time under ambient conditions, gloss (dependant on thickener type used), and mechanical properties of the paints. © 2010 Elsevier B.V. All rights reserved.
Herrera V.,Institute for Polymer Materials |
Herrera V.,Ipagsa Industrial SL |
Palmillas Z.,Institute for Polymer Materials |
Pirri R.,Arkema |
And 3 more authors.
Macromolecules | Year: 2010
Three-phase styrene-butyl acrylate composite polymer particles were synthesized by combining free radical polymerization, which yielded PS and PBA-co-PS, and controlled free radical polymerization, which yielded a large amount of PS-block-(PBA-co-PS)). Particle morphology evolves from core-shell when the particles did not contain block copolymer to hemispherical when a large amount of block copolymers was produced. The existing models could not predict this change in morphology. A general approach for the calculation of the equilibrium morphology of multiphase particles was developed using a Monte Carlo method. © 2010 American Chemical Society.