Issue 98, 2014

Preparation and characterization of flame retardant polyurethane foams containing phosphorus–nitrogen-functionalized lignin

Abstract

Lignin, a natural macromolecule containing substantial aromatic rings and abundant hydroxyl groups, was firstly chemically grafted with phosphorus–nitrogen-containing groups via a liquefaction–esterification–salification process to prepare lignin-based phosphate melamine compound (LPMC). And then the LPMC which has remaining hydroxyl groups was used to substitute parts of polyols and copolymerize with isocyanate to produce lignin-modified-PU foam (PU-LPMC) with excellent flame retardancy. Owing to the rigid aromatic structure of lignin and the covalent linkages between LPMC and the polymer–matrix, PU-LPMC showed a nearly 2-fold increase in compression strength and excellent performance of thermal stability, char residue formation, self-extinguishment and inhibition from melt-dripping and smoke generation. Moreover, a large amount of non-flammable gases were released during thermal degradation and a compact and dense intumescent (C–P–N–O)x char layer formed on the surface of the foams after combustion, resulting in the improvement of anti-flaming properties of the polymer by the flame retardancy of both gas phase and condensed phase.

Graphical abstract: Preparation and characterization of flame retardant polyurethane foams containing phosphorus–nitrogen-functionalized lignin

Supplementary files

Article information

Article type
Paper
Submitted
09 Aug 2014
Accepted
20 Oct 2014
First published
20 Oct 2014

RSC Adv., 2014,4, 55271-55279

Author version available

Preparation and characterization of flame retardant polyurethane foams containing phosphorus–nitrogen-functionalized lignin

H. Zhu, Z. Peng, Y. Chen, G. Li, L. Wang, Y. Tang, R. Pang, Z. U. H. Khan and P. Wan, RSC Adv., 2014, 4, 55271 DOI: 10.1039/C4RA08429B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements