Simple and Rapid Mechanochemical Synthesis of Lactide and 3S-(Isobutyl)morpholine-2,5-dione-Based Random Copolymers Using DBU and Thiourea

Abstract

There is a growing interest surrounding morpholine-2,5-dionebased materials due to their impressive biocompatibility as well as their capacity to break down by hydrolytic and enzymatic pathways. In this study, the ringopening (co)polymerization of leucine-derived 3S-(isobutyl)morpholine-2,5dione (MD) and lactide (LA) was performed via ball-milling using a catalytic system composed of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and 3-[3,5bis(trifluoromethyl)phenyl]-1-cyclohexylthiourea (TU). Once the homopolymerizations of MD and LA optimized and numerous parameters were studied, the mechanochemical ring-opening copolymerization of these monomers was explored. The feasibility of ring-opening copolymerizations in mechanochemical systems was demonstrated and a range of P(MD-co-LA) copolymers were produced with varying proportions of MD (23%, 48%, and 69%). Furthermore, the beneficial cocatalytic effects of TU with regards to ROP control were found to be operative within mechanochemical systems. Further parallels were observed between solution-and mechanochemical-based ROPs.

One-Pot Phenolic-Initiated Mechanochemical Synthesis of Poly(lactic acid) Nanoparticles: Application of the Artificial Neural Network Algorithm to Perform Sensitivity Assessment Models

“…All phenolic-PLA-NPs exhibited a strong, negative ζ-potential value, which is consistent with the presence of lactic acid chain ends and verifies their stability in nature . These findings imply that our approach not only allows for the preparation of phenolic-PLA polymers and nanoparticles in one step but also can be used to obtain phenolic-PLA nanoparticles with a narrow, monomodal size distribution, which is very crucial in a drug delivery synthesis. ,, …”

“…17 These findings imply that our approach not only allows for the preparation of phenolic-PLA polymers and nanoparticles in one step but also can be used to obtain phenolic-PLA nanoparticles with a narrow, monomodal size distribution, which is very crucial in a drug delivery synthesis. 17,29,42 Artificial Neural Network and Sensitivity Assessment Models. The accuracy of the artificial neural network (ANN) has been checked using two new experiments that were not trained in the ANN system.…”

The mechanochemical synthesis of polymers

“…91,99,181 Recently, Lamaty and Giani expanded the scope to the ROP of morpholine-2,5-dione using ball milling. 182 Initially, the Kim group showed that conventional organic superbase catalysts such as 1,8-diazabicyclo(5.4.0)undec-7-ene (DBU) and triazabicyclodecene can polymerise solid lactide and trimethylene carbonate without a solvent and that ball milling enables efficient initiator-catalyst mixing even at very low concentrations. The number and mass of the milling balls significantly influenced mechanochemical conversion.…”

“…91,99,181 Recently, Lamaty and Giani expanded the scope to the ROP of morpholine-2,5-dione using ball milling. 182…”

Facile synthesis of eight-membered cyclic(ester-amide)s and their organocatalytic ring-opening polymerizations

“…7,8 With the rapid development of organic catalysts in the ROP of cyclic monomers, [9][10][11][12] the organocatalytic ROP of MDs under mild conditions has been achieved recently. [13][14][15][16][17][18] Typical organocatalysts include 1,5,7-triazabicyclo [4.4.0]-dec-5-ene (TBD) and 1,8-diazabicyclo [5.4.0]undecane-7-ene (DBU)/thioureas (TUs). Besides these six-membered MDs, Hocker and Li also synthesized other types of macrocyclic (ester-amide)s by the depolymerization of PEAs and a ring enlargement strategy.…”