Colorants based on renewable resources and food-grade colorants for application in thermoplastics
Article first published online: 17 MAR 2004
Copyright © 2004 Wiley Periodicals, Inc.
Journal of Applied Polymer Science
Volume 92, Issue 5, pages 2961–2969, 5 June 2004
How to Cite
Van Den Oever, M.J.A., Boeriu, C.G., Blaauw, R. and Van Haveren, J. (2004), Colorants based on renewable resources and food-grade colorants for application in thermoplastics. J. Appl. Polym. Sci., 92: 2961–2969. doi: 10.1002/app.20298
- Issue published online: 17 MAR 2004
- Article first published online: 17 MAR 2004
- Manuscript Accepted: 8 JAN 2004
- Manuscript Received: 28 MAY 2003
- Program Bureau EET (a joint program of three Dutch Ministries: the Ministry for Economic Affairs, the Ministry for Housing, Spatial Planning and the Environment and the Ministry for Education, Culture and Science)
- Ministry of Agriculture, Nature Management and Fisheries.
- renewable resources;
- thermal properties
A series of colorants based on renewable resources and food-grade colorants have been evaluated for use in polypropylene (PP) and polyvinylchloride (PVC). It has been found that most of these colorants can be processed in PP at 200°C or even 260°C while maintaining good color intensity and color brightness. The colorants evaluated cover a large part of the color spectrum. In PP, the light stability of alizarin (red), carmine (red), indigo (blue), purpurin (red), quinizarin (red), and the aluminium lakes of quinoline yellow (yellow) and indigo carmine (blue) is close to the requirements for indoor applications. The blue colorants indigo and the aluminium lake of indigo carmine are, in principle, sufficiently light stable in PP for indoor applications. A few colorants showed bleeding from PP. Bonding of migrating colorants to the reactive carrier maleic anhydride grafted polypropylene, however, reduced bleeding of the colorant to a large extent. Also after processing in PVC at 200°C, good color intensity and saturation is maintained. Quinizarin, a structural analog of alizarin and purpurin, shows a light stability performance that is close to commercial lead chromate/molybdate orange based colorants. The best performing natural colorants are sufficiently heat and light stable for applications where moderate properties concerning heat resistance and (UV) light stability are required, such as underground PVC water drainage pipes and indoor PP applications. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2961-2969, 2004