Optimization of UV-Induced Graft Polymerization of Acrylic Acid on Polypropylene Films Using CdS as Light Sensor

Abstract

Photoconductive cell of CdS was used to optimize the photograft polymerization of acrylic acid (AA) onto polypropylene film surface. Effect of UV-light intensity on the performance of this reaction in the three-dimensional space inside the reactor was researched. A relationship between light intensity measured as conductance and performance of the AA graft reaction was found. In addition, a linear relationship (r 2 = 0.98) between the grafting degree (G) and conductance (G/wt% = (2.2 ± 0.1) 10 4 c − (0.3 ± 0.4)) was determined in the range of 5 to 20% G, where a minimum stabilization time, such as 5 min, was required. Standard deviation of the Gvalue and the conductance decreased when a longer distance between the film and the lamp was used, leading to a more homogeneous surface modification. Therefore, we propose this system as a new method to monitor and predict the performance of UV-induced reactions.

Application of surface wettability modified polypropylene nonwoven in Janus composite fibrous mats for the function of directional water transport

“…Meanwhile, during the chemical grafting, plasma or ultraviolet radiation is acted on C═C bonds of PP to form free radicals that are chemically active on the surface, then hydrophilic polar groups (such as C═O, COOH, OH) are introduced to make the material have certain wettability. This process is usually applied in the field of battery separators, surface modification of high‐performance fibers, and hydrophobic materials …”

Original antifouling strategy: Polypropylene films modified with chitosan‐coated silver nanoparticles

“…Consequently, nearly 70 mol % or less of monomers became nongrafted PAA chains, and was eliminated together with unreacted AA by rinsing. Figure also shows that the thickness of PAA‐grafted PP films increases linearly upon longer exposure time, attributed to the growth of grafted PAA backbones and the increase in film surface roughness . In addition, the surface of PP, PAA‐grafted PP, and CS‐adsorbed PP films was analyzed by attenuated total reflection infrared spectroscopy (ATR‐FTIR).…”

“…In the second step, BP* abstracts a hydrogen atom from the PP backbone, generating a new active radical (BPH). Finally, the substituent BPH was displaced and the addition of AA monomer onto PP backbones took place . During this reaction, a fraction of the monomers was involved in the AA‐photograft polymerization onto the PP chains, while the rest of monomers produced free PAA backbones by homopolymerization in the bulk or no reacted.…”

“…This ratio changes in a similar fashion to that of the G value shown in Figure , supporting the hypothesis explained above about the growth of PAA chains. In addition, at 75 s, the band ratio has a high error bar where this behavior is related to the fact that a greater degree of grafting leads to greater in‐homogeneity and roughness in terms of the growth chain of grafted PAA . There is a reciprocal dependence between the G value and the distance from the lamp to a given area of the film .…”

“…In addition, at 75 s, the band ratio has a high error bar where this behavior is related to the fact that a greater degree of grafting leads to greater in‐homogeneity and roughness in terms of the growth chain of grafted PAA . There is a reciprocal dependence between the G value and the distance from the lamp to a given area of the film . The grafting degree on the film surface is accentuated mostly below the position of the lamp (smaller distance between the lamp and the film), while the G value decreases gradually as one moves toward the edges of the film.…”