Influence of cellulose polymorphs on the polypropylene crystallization
- PDF / 511,723 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 35 Downloads / 190 Views
Influence of cellulose polymorphs on the polypropylene crystallization Slawomir Borysiak
Received: 15 October 2012 / Accepted: 25 February 2013 / Published online: 27 March 2013 Ó The Author(s) 2013. This article is published with open access at Springerlink.com
Abstract Results of the hitherto research work on alkalisation of lignocellulosic materials have been much divergent. In view of the above, the subject of this study is mercerization of cellulose from pine wood. This choice of the subject permitted observation of transformation of cellulose I to cellulose II with no participation of other components of lignocellulosic materials. According to X-ray results, during mercerization the isolated cellulose was easily (completely) transformed into cellulose II variety, while the pine wood was converted more slowly to cellulose II polymorphs. Therefore, it could be concluded that the presence of lignin and hemicelluloses in wood prevented the transformation from cellulose I to II. The main objective of this research was to establish the effect of cellulose varieties on the nucleation ability of different fillers by using differential scanning calorimetry (DSC) and polarizing microscopy. The nucleating effect of the fillers occurs only in the presence of cellulose I variety. In contrast, the presence of cellulose II variety seems to practically eliminate the nucleating effect of the fillers. Moreover, nucleation of the mercerized wood (mixture of cellulose I and II) can be also observed, but this effect is not strong. It should be emphasised that as yet no correlation has been reported between the quantitative composition of cellulose polymorphic forms (appearing not only in wood, but in cellulose isolated from wood as well) and the nucleation ability of lignocellulosic fillers.
S. Borysiak (&) Institute of Technology and Chemical Engineering, Poznan University of Technology, Sklodowskiej-Curie 1, 60-965 Poznan, Poland e-mail: [email protected]
Keywords Polypropylene Wood Cellulose Polymorphs Nucleation
Introduction Composites of polypropylene with wood have been recently given much attention at research and industry centres. It has been projected that production of such composites may soon become an important sector in plastic industry, at a level of 18 % in a year in North America and 14 % a year in Europe [1, 2]. The interest in these materials stems from interesting and specific properties of wood used as a filler of plastics [3–6]. Wood can be an alternative to the other commonly used fillers such as carbon fibres, glass fibres, silica, talk, and others. It should be emphasised that a rational approach to designing process of production of composite materials of lignocellulose materials and polymers needs analysis of such problems as thermal stability of the natural components in the process, adhesion of the components, and nucleating ability of the components. As follows from analysis of literature, the key problem in producing composite materials is a good interphase adhesion between t
Data Loading...
