# Multifunctional PCL/Lignin-PCL Composite Films for Delivery of Atrazine and Metribuzin for Sustainable Agriculture Applications

## TL;DR

This study develops eco-friendly composite films that can control the release of agricultural chemicals while offering UV protection and biodegradability.

## Contribution

The novel use of lignin-grafted PCL in composite films for controlled pesticide release and UV protection is introduced.

## Key findings

- LN-PCL films showed enhanced mechanical properties and UV light absorption.
- Controlled release of atrazine (<16%) and metribuzin (46%) was achieved over 10 weeks.
- LN-PCL films degraded within 30 days and exhibited improved surface properties.

## Abstract

Sustainable agriculture calls for the development of
eco-friendly
materials that possess desired properties and functionalities. In
this study, the effect of incorporating lignin-grafted poly­(ε-caprolactone)
(LN-PCL) into a PCL matrix was evaluated. LN-PCL was synthesized by
ring-opening polymerization (ROP), yielding polymers with varying
PCL degrees of polymerization (DP 26–101) and amphiphilic properties.
Incorporating LN-PCL into PCL films enhanced hydrogen bonding, crystallinity,
and doubled Young’s modulus. SEM analysis showed smoother surfaces
with higher DPs, while lower DPs reduced the contact angle from 78°
to 68°. LN-PCL films absorbed >98% UVAB and >94% UVC light
regardless
of DP and degraded within 30 days. Release studies indicated controlled
release rates of ATZ (<16%) and MTZ (46%) over 10 weeks. Overall,
the UV protection, surface, mechanical, and controlled release properties
of the LN-PCL/PCL films support the potential of these films as a
carrier for chemicals with applicability in agriculture.