Low temperature-dependence of N,N-dimethyl-3-methylbenzamide (DEET) release from a functional paper containing paraffin–DEET composites prepared using interfacial polymerization

Abstract

An interfacial polymerization reaction was used to prepare a functional paper with a polyamide film containing paraffin-N,N-dimethyl-3-methylbenzamide (DEET) composites, which gave a sustained release of DEET with a low temperature dependence. Preparing the polyamide film using an interfacial polymerization reaction eliminated the need for preparing microcapsules and coating the paper with a binder, which is the typical functional paper preparation method. Filter paper impregnated with an oil-water emulsion (composed of ethylenediamine and paraffin microcapsules prepared using methyl methacrylate polymer) was left in a beaker containing a cyclohexane solution of terephthaloyl chloride. The polyamide film containing paraffin-DEET composites could attach itself to the treated paper surface. We studied the release of DEET from the paper with and without paraffin, and its temperature dependence. The functional paper with paraffin showed the sustained release of DEET at high temperatures, but the release was usually inefficient. However, the sustained release of DEET was not temperature dependent, and this was found to be caused by the release of DEET being controlled by the paraffin melting. The optimum paraffin/DEET ratio was 9:1, taking into consideration the amount of DEET released from the paper and the low temperature dependence of the sustained release of DEET.

Preparation of a temperature‐responsive smart paper using a molecularly imprinted polymer and lipid bimolecular membrane

“…To prepare an oil‐in‐water emulsion and the BKC‐MIP polymer [Figure (A)], the mixture was agitated at 400 rpm with a magnetic stirrer for 10 min at 60 °C. To prepare the PA film on the paper surface [Figure (B)], filter paper (30 mm × 30 mm, pore size 5 μm) impregnated with the oil‐in‐water emulsion was immersed in 10 mL of a cyclohexane solution of TC (0.1 g) at 25 °C for 10 min, and then air‐dried at room temperature for 1 h. According to our earlier research, a reaction time of 10 min was sufficient for preparation of polyamide on the paper surface …”

“…Consequently, smart papers without binders are required. We recently investigated a number of methods for preparing smart papers without either microencapsulation or a binder, including preparing a smart paper using interfacial polymerization on the paper surface . This technique is desirable for fixing an insecticide on a smart paper.…”

Bio-Based Coatings for Paper Applications

“…Several novel intelligent responsive functional materials have been created as a coating to tune specific surface functionalities of cellulose fibers or papers, including anti-microbial paper [160,161], insect-repellant paper [162], photoactive paper [163], fragrance paper [164], and color-producing papers [165]. These papers are mostly developed by micro or nano-encapsulation techniques, where the functional responsive material is encapsulated to provide protection from ambient environment or conditions.…”

“…These papers are mostly developed by micro or nano-encapsulation techniques, where the functional responsive material is encapsulated to provide protection from ambient environment or conditions. Interestingly, these materials can respond to external stimuli such as mechanical stress [164], humidity [165], light [163], and temperature [162], and desired user properties can be achieved on demand. Especially, researchers could reversibly tune the wetting mechanisms (hydrophilic to hydrophobic and vice versa) of a liquid crystalline cellulosic film under UV light exposure, which was attributed to conformational transformation of the photo-sensitive molecules that results from the cis/trans isomerization of functional azo-groups [166].…”

Mechanism for Tuning the Hydrophobicity of Microfibrillated Cellulose Films by Controlled Thermal Release of Encapsulated Wax

“…The formation of functional papers has been reported for different applications, e.g., fragrance papers [ 12 ], anti-bacterial paper [ 13 ], insect-repellant paper [ 14 ], color-producing paper [ 15 ] and photoactive papers [ 16 ]. These papers utilize the native properties of the functional materials that were initially protected from environmental factors by microencapsulation techniques, but can also be used for the controlled release of functional materials in response to external stimuli applied such as mechanical stress [ 12 ], temperature [ 14 ], light [ 16 ] and humidity [ 15 ], as such, specifically desired “user-properties” can be delivered “on-demand”. Paper coatings can benefit from the encapsulation of kaolin clay into starch, resulting in strength increase per unit of weight [ 17 ].…”