Depth Characterization of Photopolymerized Films by Confocal Raman Microscopy Using an Immersion Objective

$29.00 plus tax (Refund Policy)

Buy Article:


The depth characterization of photopolymer films by confocal Raman microscopy is often troublesome due to refraction effects. To minimize these effects, we used an oil immersion objective and a method was developed to avoid penetration of the oil without damaging the sample surface. Since the surface may be sticky if oxygen in the air inhibits the photopolymerization, a protective layer could not be put onto the film. Therefore, the method consists in using a thin polypropylene foil as substrate for the coating and placing the sample upside down under the objective. In this manner, the immersion oil could be deposited on top of the polypropylene. The advantage of this setup is that the oil, polypropylene substrate, and photopolymer film have close refractive indices. Basic calculations showed that the depth resolution is hardly affected in that configuration and double-bond conversion profiles could be plotted as a function of reliable nominal depth. The validity of the methodology was confirmed by experiments carried out with a dry metallurgical objective on the sample surface, face up, where refraction effects are still minor. In addition, infrared spectroscopy, which was used to follow the photopolymerization, corroborated the Raman conversion of the films over their thickness. The confocal Raman microscopy method can be applied to various photopolymerized systems to characterize their behavior towards oxygen inhibition and other heterogeneities in conversion arising from inner filter effects or interactions between additives for instance.


Document Type: Research Article


Affiliations: 1: Department of Photochemistry, University of Haute Alsace, Ecole Nationale Supérieure de Chimie de Mulhouse, 3 rue Alfred Werner, 68093 Mulhouse Cedex, France 2: AkzoNobel Automotive & Aerospace Coatings BV, P.O. box 3, 2170BA Sassenheim, The Netherlands

Publication date: October 1, 2011

More about this publication?



Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more