Table 1.
A summary of Shukla’s methods and our proposed method.
Fig 1.
The particle size of homogeneous dispersed nylons.
-Nylon-6, ⋯Nylon-6,6.
Fig 2.
Monomeric rate before and after enzyme reaction of homogeneous dispersed nylon-6.
The experiments were conducted in triplicate (N = 3).
Fig 3.
Monomeric rate of formic acid caused soluble oligomerization of nylon-6 before and after Nyl series catalyzed enzymatic hydrolysis.
The experiments were conducted in triplicate (N = 3).
Table 2.
Nyl series catalyzed enzymatic monomeric of commercially available nylon after various chemical pretreatment.
Fig 4.
TLC analysis after 18% hydrochloric acid caused soluble oligomerization (before enzymatic reaction) of nylon-6 (a) and nylon-6,6 (b).
A: Ahx (monomer), B: Ald (Ahx linear dimer), C: Ahx linear oligomer, D: Sample, E: 6,6-MU, F: 6,6N-1.5mer, G: HMD, H: Sample.
Fig 5.
Monomeric rate of 50% sulfuric acid (a) or 18% hydrochloric acid (b) caused soluble oligomerization of nylon-6 before and after Nyl series catalyzed enzymatic hydrolysis.
The experiments were conducted in triplicate (N = 3).
Fig 6.
Monomeric rate of 50% sulfuric acid (a) or 18% hydrochloric acid (b) caused soluble oligomerization of nylon-6,6 before and after Nyl series catalyzed enzymatic hydrolysis.
The experiments were conducted in triplicate (N = 3).
Fig 7.
LC-MS analysis of nylon-6 before Nyl series treatment (soluble oligomerized sample induced by 18% hydrochloric acid treatment).
peak1: Ahx monomer, peak2: Ahx dimer, peak3: Ahx trimer, peak4: Ahx tetramer, peak5: Ahx pentamer.
Fig 8.
LC-MS analysis of nylon-6 after 18% hydrochloric acid treatment followed by Nyl series hydrolysis.
peak1: Ahx monomer.
Fig 9.
LC-MS analysis of nylon-6,6 before Nyl series treatment (soluble oligomerized sample induced by 18% hydrochloric acid treatment).
peak1: 6,6-monomer unit, peak2: 6,6O-1.5mer, peak3: 6,6N-1.5mer, peak4: 6,6-monomer unit dimer, peak5: 6,6O-2.5mer.
Fig 10.
LC-MS analysis of nylon-6,6 after 18% hydrochloric acid treatment followed by Nyl series hydrolysis.
A: MS positive scan of 117 (HMD), B: MS positive scan of 147 (AD).
Fig 11.
1H-NMR analysis of nylon-6 after 18% hydrochloric acid treatment followed by Nyl series hydrolysis.
A: nylon-6 sample after hydrochloric acid treatment followed by Nyl series hydrolysis, B: Authentic Ahx monomer, C: Authentic Glycerol.
Fig 12.
1H-NMR analysis of nylon-6,6 after 18% hydrochloric acid treatment followed by Nyl series hydrolysis.
A: nylon-6,6 sample after hydrochloric acid treatment followed by Nyl series hydrolysis, B: Authentic HMD, C: Authentic AD, D: Authentic Glycerol.
Fig 13.
Photographs of inside the flask before (a) and after (b) 18% hydrochloric acid caused soluble oligomerization toward used fishing net.