New effective ways of polypropylene and polylactide nonwovens functionalization

Abstract

In this study, great attempts have been made to functionalize polypropylene (PP) and polylactide (PLA) nonwovens by introducing carboxyl and amine groups onto the substrate surface. To fabricate nonwoven with carboxyl functional groups, acrylic acid (AA) was introduced to PP and PLA molecular chains through a ‘grafting from’ approach with three different methods of activation including (a) chemical initiation with an oxidizing agent, (b) photografting under ultraviolet irradiation (UV), and (c) plasma discharge (air and oxygen). The aim was to compare and find out an appropriate method to achieve a higher yield of AA-grafting on both PP and PLA nonwoven. Regarding ATR-FTIR analysis, an emerging new peak associated with stretching carbonyl bond can confirm successful AA-grafting on PP and PLA nonwovens with three methods. Moreover, based on quantitative analysis by calculated peak area under the emerging new carbonyl peak in ATR-FTIR, it was revealed that photografting under UV results in a higher peak area value indicating the higher acrylic acid grafting on both nonwovens (about 42.7/PLA and 22.7/PP) in comparison to other grafting methods. Spectrophotometer UV–visible analysis, also, confirmed that photografting yielded higher AA grafting on both PP and PLA nonwovens since grafted samples showed higher dye adsorption percentage values in comparison to the other grafted samples. In addition, to fabricate PLAs nonwoven with amine functional groups, PLAs have been aminolyzed by poly(amidoamine) dendritic material in four-time intervals at room temperature (RT) and 60 ͦ C to find out the condition of maximum PAMAM grafting. Regarding aminolyzed PLAs, emerging new peaks around 1645 cm⁻¹ associated with N–H bending vibration and double-wide peaks around 3100–3650 cm⁻¹ associated with N–H stretching vibration confirmed successful PAMAM grafting on our substrates. Furthermore, based on a calculated peak area of FT–IR analysis, the percentage of weight changes and K/S value the condition of the maximum PAMAM grafting was proposed. The findings of this research help to create a functionalized surface of textiles for future applications.

Keywords:

• Surface grafting
• acrylic acid
• dendritic material
• PAMAM
• aminolysis
• polylactide acid nonwoven
• polypropylene Nonwoven

Disclosure statement

No potential conflict of interest was reported by the authors.