Isotactic polypropylene filaments have been produced by high speed melt spinning method in the range of take-up velocity from 500 to 7, 000m/min at various extrusion temperatures. The physical and mechanical properties of as-spun fibers and their annealed fibers were studied as a function of take-up velocity. As the take-up velocity increased, the degree of crystallinity and birefringence of as-spun fibers enormously increased, and at the take-up velocities higher than 2, 000m/min, they showed levelling off at about 60% and 25×10^-3 respectively. Beyond 2, 000m/min, characteristic changes in fiber properties were also found; drastic increase in initial Young's modulus and thermal contraction, decrease in small angle X-ray scattering intensity and moreover appearance of shoulder melting peak on DSC thermograms at high temperatures. The extrusion temperature affected to some extent on the velocity regions, where the characteristic changes occurred. Various characteristic changes in the properties of the fibers spun at above 2, 000m/min were considered as the results of the changes induced on largely constrained amorphous chains trapped between crystallines when polymer molecules crystallized under high extensional stress during the spinning.

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After emerging as a full-fledged capital exporter, the three tigers (Republic of Korea (ROK), Taiwan, and Hongkong) have changed their business patterns in East-Asia (major ASEAN countries and China) since the 1990. While their projects started to cover a variety of services besides manufacturing, they have established a broader network, bridging the local business and the multinational giants from the West and Japan. With their advantage of regional business network, negotiation skill, speedy decision making by owner-managers, they have grown as a reliable partner in each different way.
The investment by ROK has followed Japanese experience as the suppliers of mass-produced hardware, and as a result, there has been competitions at the level of final products between the two. However, at the level of intermediate goods, ROK has been highly dependent on Japanese suppliers contributing to create a complimentary relationship.
In contrast to ROK, Taiwanese capitalists have served as a key player for service, including Hotel, distribution and marine transportation etc.. In manufacturing, they have also found their advantage in supplying some capital intensive products such as petrochemical, or in competitive supporting industries, to realize a better division of labor with the giants smoothly. Though this networking strategy seems similar to Singapore, the advantage of Taiwan is supported by active participation of a number of Taiwanese small business, while Singapore has had weaker initiative to be more vulnerable to the giants.
Since Hongkong had transferred most part of manufacturing process already to China, their business in the 1990s has concentrated in coordination and business organization. In increasing number of infrastructure projects in this region, such as electric power plants, road construction, or telecommunication, Hongkong has succeeded in organizing some major projects by planning and negotiating with the host government, providing financial service etc., based on their own experience.
Judging from these business patterns, the emergence of tigers have benefited the giants with a wider selection of business strategies, while tigers themselves will be benefited by the network to further sophisticate their domestic industrial structure in line with the surrounding economies.

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