# Comprehensive Analysis of Key Parameters Determining Formation and Structural Properties of Sol–Gel‐Derived Nanoporous Polymers

## TL;DR

This study explores how synthesis parameters affect the structure and properties of sol-gel-derived nanoporous polymers.

## Contribution

The work provides a rational framework for tuning aerogel/xerogel performance through controlled synthesis parameters.

## Key findings

- Phenolic monomer consumption drives gel formation and nanopore development.
- Higher cross-linking increases pore stability and reduces gel shrinkage during drying.
- Reaction temperature and time directly influence mechanical strength and pore characteristics.

## Abstract

This study presents a comprehensive investigation on the relationship between structure, synthesis parameters, and porous properties of sol–gel‐derived polymer gels. The formation of the porous gels is monitored with in situ small‐angle X‐ray scattering, in situ nuclear magnetic resonance spectroscopy (NMR), and NMR cryoporometry. The transition of the reaction solution to a solid gel is governed by the consumption of the phenolic monomer. Primary particle growth and nanopore formation proceed during this short time period and are completed when all resorcinol is consumed. The kinetics of these processes are temperature‐dependent and they are completed within 12 min at 120 °C and within 60 min at 80 °C. Extending the reaction time further results in enhanced cross‐linking of the polymer, as observed by solid‐state 13C NMR spectroscopy. Extended reaction time, i.e., higher degree of polymer cross‐linking, enhances pore stability and reduces gel shrinkage during drying, resulting in xerogels with larger pore volume, larger external surface area, and larger average pore sizes. This work rationalizes molecular‐scale transformation of polymers with macroscopic properties, thus providing a rational tool for tuning aerogel/xerogel performance through synthesis design.

A comprehensive study shows that chemical composition of the gelation mixture determines the primary particles size and the size of pores they form. Reaction temperature and time define the degree of cross‐linking within the polymer and thus determine the mechanical strength of the gel. High mechanical strength results in low degree of shrinkage during thermal drying.© 2026 WILEY‐VCH GmbH