Graft copolymers having hydrophobic backbone and hydrophilic branches. XVIII. Poly(styrene) nanospheres with novel thermosensitive poly(N-vinylisobutyramide)s on their surfaces

Liu

et al. 2019

ACS Appl. Bio Mater.

We developed a facile synthesis for a series of multifunctionalized polyesters by Passerini three-component polymerization (Passerini-3CP) in a “one-pot” method at room temperature using serial dicarboxylic acids, dialdehyde, and tert-butyl isocyanide as monomers. First, the effects of monomer feed ratio, monomer concentration, and different dicarboxylic acids involved in the polymerization were systematically investigated. The in situ FTIR and GPC measurements have suggested a step-growth mechanism for Passerini-3CP. Second, five succinic acid end-capped polyethylene glycols (S-PEGs) with different molecular weights of 400, 800, 1000, 2000, and 4000 g/mol were prepared and selected as dicarboxylic acids for the subsequent Passerini-3CP to fabricate the thermosensitive and biocompatible polyesters. Among the five resulting polyesters, four polyesters from S-PEG-400, S-PEG-800, S-PEG-1000, and S-PEG-2000 show reversible response to the external temperature, and the lower critical solution temperature (LCST) in water is in the range of 28.5–84.2 °C. Through the copolymerization of S-PEG-400 and S-PEG-800, the LCSTs for functional polyesters can be conveniently controlled to be 38.7, 42.3, and 58.0 °C, respectively. After 24–72 h of incubation in polyester solution, the viability rate of HeLa cells reached up to 80–107%, showing its excellent biocompatibility. The cleavable polyesters were also prepared by integrating S–S bonds onto their backbones in Passerini-3CP of 3,3′-dithiodipropionic acid as one comonomer for the biomedical applications. With the aid of the hydrophobicity of doxorubicin (DOX) and thermosensitivity of polyesters, the doxorubicin-loaded carriers with the size of 200–400 nm and core–shell structure were easily obtained by dialysis below LCST and subsequent heating to LCST. The effective release of DOX from the carriers can be triggered by the characteristic reaction of l-glutathione (GSH) with S–S bonds in the functionalized polyester backbones.

Section: Resultssupporting

confidence: 91%

Facile Synthesis and Properties of Multifunctionalized Polyesters by Passerini Reaction as Thermosensitive, Biocompatible, and Triggerable Drug Release Carriers

Liu

et al. 2019

ACS Appl. Bio Mater.

Macro Chemistry & Physics

“…That is, when the M n of PEP-5% were controlled at 11.5, 13.2, 15.4, 16.6, 23.3, 32.3, and 42.6 kDa, the LCSTs were measured as 34.1, 28.8, 25.9, 23.7, 21.1, 19.7, and 18.9 °C, respectively. These results are exactly the same as the reported results for other thermosensitive polymers, such as poly(N-vinyl isobutylamide) [42] and poly(carbonate ether). [43] One important reason can be the fact that more H-bonding formed among PEPs chains via amides with the increase of their M n .…”

Section: Regulation Of Thermosensitivity For Pmp and Pepsupporting

confidence: 90%

Synthesis of Temperature and Light Sensitive Copolymers with Controlled Aggregation during Phase Transitions

Ding

Zhang

et al. 2019

Two thermosensitive copolymers of acrylates (PMP/PEP) and a thermo/light sensitive copolymer of acrylate with acrylamide (PMABz) are synthesized via a ring‐opening reaction and subsequent radical polymerization using a facile one‐pot method. The lower critical solution temperature (LCST) of PMP and PEP shows a dependence on the content of the structural unit and can be easily tuned to 18–35 °C by mercaptoethanol‐mediated control of the molecular weight. The isomerization of PMABz can be reversibly induced by alternating irradiation at 365 nm to produce the cis form and at 254 nm to produce the trans form. The LCST of cis‐PMABz (40.3 °C) is significantly higher than that of trans‐PMABz (37.8 °C) because of its higher hydrophilicity. Furthermore, the particle size of aggregated PMABz can be controlled from 665 nm (for the cis form) to 996 nm (for the trans form) during the heating run. After quenching the PMABz solution, PMABz particles have repeating patterns, such as leaf veins or hollow containers, indicating their potential applicability.

J of Applied Polymer Sci

“…Carboxyl‐terminated NIPAm‐BA copolymeric oligomer (Scheme ) employed as the precursor of macromonomer was prepared based on the method described in the literatures 23, 36…”

Section: Methodsmentioning

confidence: 99%

Study on micellization of poly(N‐isopropylacrylamide‐butyl acrylate) macromonomers in aqueous solution

Zheng

Shi

Xia

et al. 2010

A kind of thermo-sensitive macromonomer, styrene-terminated poly(N-isopropylacrylamide-butyl acrylate) [P(NIPAm-BA)] has been synthesized in this work. With the help of ultraviolet spectrum (UV), proton nuclear magnetic resonance ( 1 H-NMR), potentiometric titration and dynamic light scattering (DLS), the molecular structure, thermo-sensitive characteristics, and micellization behaviors of this kind of macromonomer have been investigated. The obtained results demonstrate that, the molecular structure of thermo-sensitive macromonomer, including the content of comonomer unit on the backbones and the variety of terminal groups, has great influence on its low critical solution temperature (LCST) and critical micelle concentration (CMC).