Titanium butoxide ti obu 4

Adipic acid (AdA, with purity above 99.5%), poly(phosphoric acid) (PPA), 1,3-propanediol (1,3-PDA) (purity: >99.6%), titanium butoxide (Ti(OBu)₄, with purity of 97.0%) used as catalyst, and PLA (with mean M_n = 20,000 Da and polydispersity index (PDI) ≤ 1.3) were purchased from Sigma Aldrich Chemical Co. (Steinheim, Germany). Poly(vinyl alcohol) (PVA) with average M_w varying between 31,000 Da and 50,000 Da, 87%–89% hydrolyzed was also percussed from Sigma Aldrich Chemical Co. (Steinheim, Germany). Rhizopus delemar and Pseudomonas cepacia were purchased from BioChemika (Steinheim, Germany). Risperidone Drug, with particle sizes of D(0.10) = 10 μm, D(0.50) = 100 μm, and D(0.90) = 200 μm, was kindly donated by Pharmathen S.A. (Athens, Greece). All other reagents and solvents used for the analytical methods were of analytical grade.

We purchased 2,5-thiophene dicarboxylic acid (TDCA) (purity > 99.5%), 1,6-hexanediol (1,6-HDO, 99%), and 1,4-Bis(2-hydroxyethyl)benzene (BHB, 99%) from Aladdin Reagent Co. Ltd., Shanghai, China. Titanium butoxide (Ti(OBu)₄) (purity > 97.0%) was purchased from Sigma Aldrich Chemical Co., Ltd. (Shanghai, China). Solvents such as methanol, ethanol, and chloroform (purity > 99%) were purchased from Sinopharm Chemical Reagent Co. Ltd., Zhejiang, China. Porcine pancreatic lipase (PP-L) with activity > 55 U/mL was purchased from Sigma-Aldrich, Taufkirchen, Bavaria State, Germany, and cultured in a dark, humid container for a period of time prior to its utilization.

Adipic acid (AdA) (purity >99.5%) and 1,3-propanediol (1,3-PD) (purity > 99.6%) were purchased from Fluka (Steinheim, Germany). Titanium butoxide (Ti(OBu)₄, purity: >97.0%), was purchased from Sigma Aldrich Chemical Co (Steinheim, Germany). L-Lactide (LA) Purlact B3 (purity 99% w/w, stereochemical purity in L-isomer 95% (w/w) was purchased from Corbion N.V. (Gorinchem, The Netherlands) and Tin(II) 2-ethylhexanoate (Sn(Oct)₂, purity > 92.5%) from Merck KGaA, (Darmstadt, Germany).