de Freitas Amanda S M, Rodrigues Jéssica S, Fré Lucas V B, Vieira Henrique O S, Nascimento Maria E S, Amaro Stefanny F, Emidio Livia S, de Araujo Daniele R, Sepulveda Anderson F, Komatsu Daniel, Botaro Vagner R, Fraceto Leonardo F, Ferreira Marystela
Science and Technology Center for Sustainability (CCTS), Federal University of São Carlos (UFSCar), João Leme dos Santos, km 110, 18052-780 Sorocaba, SP, Brazil; Institute of Science and Technology, São Paulo State University (UNESP), Av. Três de Março 511, 18087-180 Sorocaba, SP, Brazil.
Institute of Science and Technology, São Paulo State University (UNESP), Av. Três de Março 511, 18087-180 Sorocaba, SP, Brazil.
Int J Biol Macromol. 2025 Jun;314:144386. doi: 10.1016/j.ijbiomac.2025.144386. Epub 2025 May 19.
Kraft lignin (KL) and its acetic acid-fractionated derivatives were evaluated for their antioxidant and ultraviolet C (UV-C)-absorbing properties to mitigate the photooxidative degradation of polyvinyl alcohol (PVA). PVA films were prepared with 4 % (w/w) KL macroparticles - including unfractionated KL and the fractionated forms KL30, KL40, and KL50 - and with 0.4 % (w/w) lignin nanoparticles (NP), derived from the same fractions (named NPKL, NP30, NP40, and NP50). All formulations, including the control (pure PVA), were blended with 10 % (w/w) NPK fertilizer (nitrogen‑phosphorus‑potassium, 10-10-10) and plasticized with glycerol for film casting. After 21 days of UV-C exposure, films containing LNP retained over 90 % transparency, compared to ~70 % for pure PVA. Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) confirmed reduced photooxidative and thermal degradation in lignin-containing films, especially those with KL30 and NP30. Biodegradation assays using respirometric CO₂ analysis showed accelerated release for NP30 (up to 90 mg after 20 days), reflecting enhanced microbial activity. Leaching assays demonstrated controlled release of NPK ions over 40 days in films with NP. In mulch film application tests with cherry tomato, PVA + NP30 showed seedling development comparable to commercial mulch and superior to control films. These results confirm the potential of NP as sustainable, multifunctional additives for UV stabilization and controlled nutrient delivery in biodegradable agricultural films.
评估了硫酸盐木质素（KL）及其乙酸分级衍生物的抗氧化性能和紫外线C（UV-C）吸收性能，以减轻聚乙烯醇（PVA）的光氧化降解。用4%（w/w）的KL大颗粒（包括未分级的KL以及分级形式的KL30、KL40和KL50）和0.4%（w/w）源自相同级分的木质素纳米颗粒（NP，命名为NPKL、NP30、NP40和NP50）制备PVA薄膜。所有配方，包括对照（纯PVA），均与10%（w/w）的NPK肥料（氮-磷-钾，10-10-10）混合，并使用甘油增塑以进行流延成膜。在UV-C照射21天后，含LNP的薄膜保留了超过90%的透明度，而纯PVA的透明度约为70%。傅里叶变换红外光谱（FTIR）和差示扫描量热法（DSC）证实含木质素薄膜中的光氧化和热降解减少，尤其是含KL30和NP30的薄膜。使用呼吸计CO₂分析的生物降解试验表明NP30的释放加速（20天后高达90毫克），反映出微生物活性增强。浸出试验表明含NP的薄膜在40天内NPK离子可控释放。在樱桃番茄的地膜应用试验中，PVA + NP30的幼苗发育与商业地膜相当，且优于对照薄膜。这些结果证实了NP作为可生物降解农用薄膜中用于紫外线稳定和控制养分释放的可持续多功能添加剂的潜力。
