An initial reply to Daniel Dudasko's comments on Orientation of Films-Part 1

Daniel comments: “Very informative article, but much too general, please comment on which is better - MDO or MD/TD orientation. If we compare "mono" and "MD/TD" technology, which technology is better or compare it. Pleases compare in-line and off-line MDO technology.”

Of course, there is no single right answer to this question about which is better, MDO or MD/TD orientation and it has been under investigation, at least for polymers, for longer than I have been alive and will likely continue after I am gone to my reward. The context of the question has to be set so that the best answer for the situation can be developed. The “best” answer will revolve around cost and structure property relationships developed by the MDO and MD/TD processes relative to the application.

For instance, in the case of strapping, MDO orientation alone would be better than MD/TD because the application requires ultimate MD strength and a weak TD is not that important to the application. At the same time, a highly oriented MD-only sheet may be too weak in the TD to perform well in a packaging application, and here a MD/TD orientation is more desirable. However, if the MD-only film was laminated to a cast film then it might be adequate in the application for the desired cost of the film relative to the sales price acceptable to the customer. 

However, in the days ahead, I will continue to comment on the differences between the two processes in various situations