# PVDF/PGMA Blend Membranes: NIPS-Driven Microstructure, Thermodynamic Miscibility, and Enhanced Wettability

## TL;DR

This paper shows how blending PVDF with PGMA improves membrane properties like wettability and crystallinity for biomedical use.

## Contribution

The study introduces a novel PVDF/PGMA blend system with tunable microstructure and enhanced β-phase crystallinity via NIPS.

## Key findings

- PVDF/PGMA blends exhibit partial miscibility with phase separation at ~37 vol% PGMA.
- NIPS processing increases PVDF β-phase content from 17% to 70% in optimized blends.
- PGMA incorporation enhances porosity and surface hydrophilicity of membranes.

## Abstract

Novel poly­(vinylidene fluoride) (PVDF)/poly­(glycidyl
methacrylate)
(PGMA) blend membranes were successfully fabricated via the nonsolvent-induced
phase separation (NIPS) process. Theoretical prediction using the
Schneier equation and comprehensive characterization (XRD, FTIR, DSC,
FESEM) established that the system exhibits partial miscibility with
a critical phase separation threshold around 37 vol % PGMA. Below
this threshold, good polymer miscibility was evidenced by favorable
thermodynamic parameters and spectroscopic shifts. Beyond it, clear
macroscopic phase separation occurred, influencing crystal uniformity
and morphology. Crucially, the NIPS process strongly promoted the
crystallization of PVDF into the polar, electroactive β-phase.
The β-phase content was significantly enhanced from 17% in neat
PVDF powder to a maximum of 70% in the optimized blend, despite the
overall degree of crystallinity remaining relatively low (26–31%).
Moreover, melting the NIPS-formed blends further enhanced the β-phase
content at low-to-mid PGMA concentrations. Beyond the crystalline
phase modulation, PGMA incorporation effectively modulated the membrane
microstructure, significantly enhancing both porosity and surface
hydrophilicity. The demonstrated ability to tune the microstructure
and polar phase formation through simple blend composition makes these
PVDF/PGMA membranes highly promising candidates for advanced functional
and biomedical applications.