Furthermore, HIPS exhibited greater pillar heights over HCCPS. The HIPS, which has an elastic modulus of more than 2.5 times less than that of HCCPS, was able to undergo relatively more strain owing to its higher compliance (or lower resistance to strain).
Given that HCCPS had a MFI value four times that of HIPS, it was expected that HCCPS would fill the microholes much more easily, and that it would take higher temperatures to allow HIPS to exhibit similar filling.
Moreover, it was seen that although HIPS had a significantly lower MFI, it did not exhibit a lack of filling compared with HCCPS. Additional research seeks to confirm the mechanism behind the increased aspect ratios, and to determine optimum conditions to ensure filling and proper demolding of all polymer pillars.