Functionalization of a Cylindrical Pore Membrane by Plasma Graft Polymerization

AbstractBioactive ceramics are promising candidates as 3D porous substrates for bone repair in bone regenerative medicine. However, they are often inefficient in clinical applications due to mismatching mechanical properties and compromised biological performances. Herein, the additional Sr dopant is hypothesized to readily adjust the mechanical and biodegradable properties of the dilute Mg-doped wollastonite bioceramic scaffolds with different pore geometries (cylindrical-, cubic-, gyroid-) by ceramic stereolithography. The results indicate that the compressive strength of Mg/Sr co-doped bioceramic scaffolds could be tuned simultaneously by the Sr dopant and pore geometry. The cylindrical-pore scaffolds exhibit strength decay with increasing Sr content, whereas the gyroid-pore scaffolds show increasing strength and Young’s modulus as the Sr concentration is increased from 0 to 5%. The ion release could also be adjusted by pore geometry in Tris buffer, and the high Sr content may trigger a faster scaffold bio-dissolution. These results demonstrate that the mechanical strengths of the bioceramic scaffolds can be controlled from the point at which their porous structures are designed. Moreover, scaffold bio-dissolution can be tuned by pore geometry and doping foreign ions. It is reasonable to consider the nonstoichiometric bioceramic scaffolds are promising for bone regeneration, especially when dealing with pathological bone defects.

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Use of radiation graft polymerization for synthesizing and modifying gas-separating membranes—review

Polymer Science U S S R ◽

10.1016/0032-3950(91)90311-d ◽

1991 ◽

Vol 33 (7) ◽

pp. 1259-1285

Author(s):

S.A. Pavlov ◽

E.N. Teleshov

Keyword(s):

Graft Polymerization

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Preparation of Superhydrophobic Fabric Based on the SiO 2 @PDFMA Nanocomposites by an Emulsion Graft Polymerization and a Hot‐Pressing Process

ChemistrySelect ◽

10.1002/slct.202100848 ◽

2021 ◽

Vol 6 (22) ◽

pp. 5646-5654

Author(s):

Xiaoli Liu ◽

Youcai Gu ◽

Tengfei Mi ◽

Yuehua Zhao ◽

Xiaomei Wang ◽

...

Keyword(s):

Hot Pressing ◽

Graft Polymerization ◽

Pressing Process

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Radiation-Induced Asymmetric Grafting of Different Monomers into Base Films to Prepare Novel Bipolar Membranes

Molecules ◽

10.3390/molecules26072028 ◽

2021 ◽

Vol 26 (7) ◽

pp. 2028

Author(s):

Shin-ichi Sawada ◽

Yasunari Maekawa

Keyword(s):

Acrylic Acid ◽

Anion Exchange ◽

Graft Polymerization ◽

The Other ◽

Practical Applications ◽

Bipolar Membranes ◽

Graft Polymers ◽

Grafting Reactions ◽

Radiation Induced

We prepared novel bipolar membranes (BPMs) consisting of cation and anion exchange layers (CEL and AEL) using radiation-induced asymmetric graft polymerization (RIAGP). In this technique, graft polymers containing cation and anion exchange groups were introduced into a base film from each side. To create a clear CEL/AEL boundary, grafting reactions were performed from each surface side using two graft monomer solutions, which are immiscible in each other. Sodium p-styrenesulfonate (SSS) and acrylic acid (AA) in water were co-grafted from one side of the base ethylene-co-tetrafluoroethylene film, and chloromethyl styrene (CMS) in xylene was simultaneously grafted from the other side, and then the CMS units were quaternized to afford a BPM. The distinct SSS + AA- and CMS-grafted layers were formed owing to the immiscibility of hydrophilic SSS + AA and hydrophobic CMS monomer solutions. This is the first BPM with a clear CEL/AEL boundary prepared by RIAGP. However, in this BPM, the CEL was considerably thinner than the AEL, which may be a problem in practical applications. Then, by using different starting times of the first SSS+AA and second CMS grafting reactions, the CEL and AEL thicknesses was found to be controlled in RIAGP.

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