University, firm partner to make footwear textiles from industrial waste

Kaohsiung, Nov. 22 (CNA) National University of Kaohsiung (NUK) said Monday that it has been working with a company in the semiconductor industry to produce a type of textile from waste in that sector, which is now being used to make shoes.

The material that has been successfully produced is suitable for making shoe soles, said NUK, which has been partnering ASE Technology Holding Co., a leading IC packaging and testing services provider.

Research teams at NUK and Advanced Semiconductor Engineering (ASE) determined that the plastic components of the adhesive tape used specifically for semiconductor wafer dicing were recyclable, and they found a way to process it so that it could be used in footwear manufacturing, the university said in a statement.

The process is known as the granulation of thermoplastic olefin (TPO), which is a combination of polymer and filler blends like polypropylene, an elastomer or rubber, and a filler such as calcium carbonate, according to the statement.

The granulation process allows for a reduction of the material so it can be used for footwear manufacturing, the NUK said.

Taiwan's electronics factories generate about 200 metric tons of waste each year, and collaboration between the university and the industrial sector has led to the development of new techniques for converting the waste into materials for shoe sole production, according to the university.

The TPO produced by the NUK and ASE research teams has been adopted by Puhu Footwear Co., Ltd. in Kaohsiung to make shoe soles, replacing the commonly used ethylene-vinyl acetate (EVA), the university said.

In the statement, Puhu Footwear Manager Hsueh Po-hsiang (薛博祥) is cited as saying that in order to switch from EVA to TPO, it had to adjust its molds and parameters and make several revisions to fine tune the production process.

The company is now making shoe soles that are 55 percent TPO, without compromising basic requirements such as balance and shock absorption, Hsueh said.

The TPO research teams were led by Su Chean-cheng (蘇進成), head of NUK's Department of Chemical and Materials Engineering, and C.P. Hung (洪志斌), vice president of the Corporate R&D Center at ASE, according to the statement.