Styrene st

Styrene (St) (Pure ≥ 99%, Sigma-Aldrich, St. Louis, MO, USA) and methyl methacrylate (MMA) (99%, Sigma-Aldrich) were purified by passing through a column pack with neutral and basic aluminum oxide (Purum, Fluka, Honeywell, NC, USA). Acrylic acid (AA) (ACS reagent, Sigma-Aldrich) was distilled before use. Divinyl benzene (DVB) (Technical grade 80%, Fluka), poly (vinyl alcohol) (PVA) (Mw = 58000–124,000, Sigma-Aldrich), potassium persulfate (KPS) (ACS 99%, Fluka), potassium hydroxide (KOH) (85%, Sigma-Aldrich), oleic acid (OA) (Pharma grade, Panreac, ITW, Glenview, IL, USA), hexadecane (HD) (99%, Sigma-Aldrich), sodium dodecyl sulfate (SDS) (98.5% GC, Sigma-Aldrich), and zinc acetate dehydrate (Zn (CH₃COO)₂·2H₂O) (98%, Sigma-Aldrich) were used as received. Ethanol (95%, RCI Labscan, Bangkok, Thailand), cyclohexane (≥99.8%, Sigma-Aldrich), and deionized (DI) water were applied throughout the work.

Styrene (ST) (Sigma-Aldrich, St. Louis, MO, USA) has been purified through vacuum distillation. 2-Hydroxyethyl methacrylate (HEMA) (Sigma-Aldrich, St. Louis, MO, USA) and glycidyl methacrylate (GMA) (Merck, Darmstadt, Germany) have been purified by passing over short columns of activated basic alumina. Potassium persulfate (K₂S₂O₈) (KPS) (Merck, Darmstadt, Germany) has been recrystallized from an ethanol/water mixture and then vacuum-dried. β-cyclodextrin (BCD-OH) (≥95.0%, Wacker Chemie, Munich, Germany) was vacuum-dried before use for 24 h. p-Toluene sulfonyl chloride (Ts-Cl) (reagent grade, ≥98%, Merck, Darmstadt, Germany), sodium hydroxide (reagent grade, ≥98%, pellets (anhydrous), (Sigma-Aldrich, St. Louis, MO, USA), 1,4-Diaminobutane (99%, Sigma-Aldrich, St. Louis, MO, USA), acetone (for analysis, >99%, Chemical Company Iasi), dimethyl sulfoxide (DMSO) (Aldrich-anhydrous, Darmstadt, Germany), pyridine (Aldrich, Darmstadt, Germany), glucose (Aldrich anhydrous, Darmstadt, Germany), phenol (Merck, Darmstadt, Germany), sulfuric acid (Sigma-Aldrich, St. Louis, MO, USA), bisphenol A (Merck, Darmstadt, Germany), ethanol (Chimopar, Bucuresti, România) were used as received.

Polyhydroxybutyrate (PHB), marketed under the code FE-113, with a melt flow index (MFI) of 30 g/10 min (2.16 kg/190 °C—ASTM D-1238) and M_w = 340 kg/mol, is produced by PHB Industrial SA (Brazil). Maleic anhydride (MA) with 95% purity was used as a functional group in the form of flakes, manufactured by Sigma Aldrich. Dicumyl peroxide (DCP) was used as a free radical initiator in powder form with 98% purity and manufactured by Sigma Aldrich. Styrene (St) was used as a comonomer with 99% purity and was manufactured by Sigma Aldrich. Tin(II) 2-ethylhexanoate (Sn(Oct)₂) was used as a catalyst with 99% purity and manufactured by Sigma Aldrich.