Answer:
AIES CO., LTD., which is actually recycling plastic bottles, kindly answered the question above.
 
 
A plastic bottle is made of a polymer called “polyethylene terephthalate (PET)”. Approximately 100 molecules of terephthalic acid (TPA) and ethylene glycol (EG, structure: HO-CH₂-CH₂-OH) link alternately to form this compound’s structure. PET cannot be dissolved in acetone. However, when alcohol (compound which has –OH group at the end) comes near the chemical bond between TPA and EG (ester bond), EG easily loses its position to the alcohol. This is called “ester exchange”. If this reaction happens between TPA and EG, this also means that the chain of PET polymer shortens. This property is used for breaking down PET. The short chain of PET will easily dissolve in EG.
  
We developed “AIES process” for recycling plastic bottles. In this process, PET is broken down into bis-2-hydroxyethyl terephthalate (BHET), which is monomer, by the method above. After BHET is well purified, PET is re-synthesized using BHET. It is important to purify BHET very well, because a high-grade monomer is necessary for the synthesis of long-chain polymers. If people try to recycle plastic bottles without using the AIES process, they must convert BHET to a molecule called “dimethyl terephthalate (DMT)”, then refine the DMT, and finally convert the DMT to BHET again. 
  
One of the engineers in our company, who developed the AIES process, said that he first did the experiment in his kitchen at home. Now this technology is housed in a big plant whose processing capacity is 27500 tons. This growth shows what motivation can do.
 
 
Acknowledgement
AIES CO., LTD.
They developed the unique technology for recycling plastic bottles. Please take a look at their website for details.
    
 

This article is translated by Chemistryquestion.com from the original article in Chemistryquestion.jp.  Please let us know if you find any errors.