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An evaluation method for the stretchability of a biaxially oriented film during the stretching process was recently developed using an in situ measurement test machine. Stress, retardation, three-dimensional refractive indexes, light-scattering image, and birefringence distribution of films could be obtained in a short time. This stretching test machine was applied to examine the film stretchability of both semicrystalline polymers, such as polypropylene, and noncrystalline polymers, such as polystyrene, under various preheating times. From the measurements, the stress of semicrystalline polymers increased with increasing preheating times before stretching the film. However, the stress of noncrystalline polymers did not increase with increasing preheating times. This means that semicrystalline polymer is required to set up an optimum stretching condition of the preheating time for a satisfactory biaxially oriented film. Furthermore, the birefringence distribution and thickness uniformity of the stretched film were measured simultaneously. It was found that the stretchability of polypropylene and polystyrene films could be evaluated with a small piece of the sample using the biaxial stretching test machine.

The evaluation method for a biaxially oriented film was developed using in-situ measurement during the stretching process. It can obtain basic data such as stress-strain curves, birefringence, light scattering, three dimensional refractive indexes and birefringence distribution. Stress and strain as functions of stretching speed and stretching temperature, as well as the deformation of spherulite of semi-crystalline polymer can be obtained by measuring the birefringence and light scattering during the biaxial stretching process with a small piece of polymer sample. The experimental results show the stress, retardation and three dimensional molecular orientations behavior during the simultaneous biaxial stretching and the sequential biaxial stretching process. Stretchability, thickness uniformity and spherulite size can be obtained simultaneously. In this paper, advantages and details of the newly developed system will be discussed with some experimental data.

The evaluation method for a biaxially oriented film was developed using in-situ measurement during the stretching process. It could obtain basic data such as stress-strain curve, birefringence, light scattering, three-dimensional refractive indexes and birefringence distribution as functions of time, temperature and percentage in elongation, the information of superstructure could be obtained by measuring the birefringence and light scattering during the biaxial stretching process with a small piece of polymer sample. From the experimental results, stretchability, thickness uniformity and spherulite size could be evaluated simultaneously. Furthermore, as the thickness uniformity is closely related to the standard deviation of birefringence distribution, the thickness uniformity can be also evaluated by the retardation distribution

A cat excreting Echinococcus multilocularis eggs was recently identified in Hokkaido, representing the first such observation in Japan. The cat was raised free-range and frequently ate rodents. Fecal egg examination revealed eggs of taeniids (EPG: 440) and Spirometra spp. (EPG: > 1000). PCR targeting part of the mitochondrial cytochrome c oxidase subunit I gene of E. multilocularis was positive with DNA from 3 single isolated taeniid eggs, and sequence analysis of one amplicon confirmed E. multilocularis. The results indicated that the eggs of E. multilocularis distributed in Hokkaido can be excreted in cat feces, and suggested the necessity of further studies to clarify whether the eggs excreted in cat feces are infective and thus whether cats can serve as infectious source to humans in Japan.

An automatic rapid elongation system for polymer films is provided in the optical birefringence measurement system using phase modulation technology. It can measure optically and dynamically modular deformation in polymer films during rapid elongation process and stress relaxation after the completion of elongation. Micro and macroscopic information on the deformation in molecules of polymer films can be obtained by measuring birefringence retardation, stress and elastic modulus as the function of time, temperature and percentage of elongation. Advantages, details of the system and some data obtained are described.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.