Waterproof Coating Material

Development of Waterproof Coating Material and High-Performance Shoe Adhesive

Abstract

Waterproof materials are chemical-based and provide temporary solutions. They are also costly and create permanent deformation issues on shoe surfaces. One of the most important areas for the footwear industry is adhesives. Adhesives are an interface material that binds objects together. These chemical-based adhesives have significant importance for shoe longevity. We are in constant motion in daily life, which is why shoes continuously undergo deformation. Furthermore, shoes experience more severe deformations under difficult contact conditions, with surfaces and soles and upper/side sections separating from each other. To address these types of problems, many organizations are pursuing various approaches to produce ideal adhesives. For this purpose, in our study, a high-performance adhesive and coating material providing waterproofing properties in shoe products have been obtained.

1. Introduction

Adhesive is a natural and synthetic substance that bonds objects and surfaces together. Many adhesives are produced for specific purposes depending on the sector and the sublayers that need to be bonded. Adhesives are mostly made from polymers or resins, which are chemical structures that can be recognized as plastic in the end. Each adhesive has its own unique formula. When needed, adhesive varies according to the material. Adhesives can be examined in three main categories: natural adhesives, semi-synthetic adhesives, and synthetic polymers [1,2]. Natural Adhesives: In ancient times, natural adhesives were obtained from plants and by processing animal parts such as bones, skin, and secretory glands. Animal adhesives were preferred more in rough work and areas requiring strong adhesive properties, while plant-based adhesives (such as starch) were used in more delicate work like paper bonding. In the Middle Ages, animal-based natural adhesives were obtained from the fats, nerve tissue, tendons, and bones of large livestock such as cattle, bulls, and buffalo. Recent studies have also produced stronger natural adhesives. Plant-Based Adhesives: Mostly created by processing starchy plants. In addition to starch, resins from certain tree species are also plant-based adhesives. Starch is a polymeric material with high molecular weight. It is found abundantly in substances such as wheat and potatoes. Starch is a polymer of glucose and is applied in cold form and has no odor. On the other hand, starch is not a strong adhesive and has low water resistance. It is processed to increase its resistance. Dextrin (a sticky substance obtained from starch breakdown), obtained through starch degradation by heating, is more moisture-resistant than starch. For this reason, dextrin is preferred over starch. There are three types of dextrin: white dextrin, yellow and canary dextrin, and British gum. When barks is added to dextrin, its adhesiveness and durability increase. During the Ottoman period in Anatolia, an adhesive called çiriş was used in tannery and leather shoe making instead of adhesives like derby and bally used today. This adhesive is obtained from dextrin found in the roots of çiriş, a white-flowered plant from the lily family. Protein-Based Adhesives: Among protein-based adhesives produced from animal parts such as bones, skin, and gills, the most widely used in protective applications is what is known today as animal glue. Animal glue is made from animal bones and skin, has a dark purple and brown color tone, and is a gelatinous adhesive applied after dissolving in water.   Adhesives Used in Shoe Manufacturing: • Hotmelt Adhesive, • Solvent-Based Polychloroprene Adhesive (Derby), • Solvent-Based Elastomer-Based Adhesive, • Solvent-Based Polyurethane Adhesive, • Single-component, polychloroprene-based, water-based adhesive [1,2].   In addition to adhesives, one of the most important aspects is waterproofing products. These chemically-based materials, when sprayed on shoe surfaces, provide protection lasting several hours, repelling incoming liquid and exhibiting hydrophobic, or water-repelling, properties. However, there are common misconceptions. Those produced with water-repellent technology are also water-resistant but are not as effective in shoe protection as waterproofing properties. Some waterproof shoes do not breathe either. Models suitable for outdoor sports exist. They keep the foot warm in winter months and do not create a feeling of dampness. Thanks to shoe technologies, production with different properties takes place. The type of season and weather conditions in which the shoe will be used will affect technology selection. Among the best-known shoe technologies is waterproofing, another known term being waterproof properties. [caption id="attachment_143952" align="aligncenter"] Figure 1. Waterproofing and shoe adhesive[/caption] Waterproof shoes are used mainly in winter and spring months. In winter and autumn months, interest in waterproof boots is quite high. In spring, shoes are preferred instead of boots [3]. Waterproofing and shoe adhesive are shown in Figure 1. [caption id="attachment_143953" align="aligncenter"] Figure 2.1. Our waterproof coating material and test studies[/caption] In this study, a high-performance adhesive and coating material providing waterproofing properties in shoe products have been obtained.

2. Material and Method

2.1. Material

Citric acid-coated calcite, silica, aerogel and our proprietary matrix material, and high-performance rapid adhesive with our proprietary formula were selected as waterproofing materials.

2.2. Method

A mixture was prepared using citric acid-coated calcite 3-7.5%, silica 1-5%, aerogel 1-5% and our proprietary matrix material, and spraying was applied at a specific flow rate onto summer and winter shoes using a spray gun. After waiting half an hour, water was passed through intensively and waterproofing performance was measured [4]. Our waterproof coating material and test studies are shown in Figure 2.1. Our high-performance rapid adhesive with proprietary formula was injected into the torn section of the shoe sole and allowed to quickly bond with the upper material, with complete hardening achieved in 15 minutes [5]. Our high-performance shoe adhesive application with our proprietary formula is shown in Figure 2.2. [caption id="attachment_143954" align="aligncenter"] Figure 2.2. Our high-performance shoe adhesive application with our proprietary formula[/caption]  

3. Results and Discussion

In this study, a high-performance adhesive and coating material providing waterproofing properties in shoe products have been successfully obtained. Despite passage through water-filled terrain, the absence of penetration into the inner shoe surface and the prevention of water accumulation on the shoe strongly suggest that this material will shed light on the future. Testing of our study will be conducted under other conditions as well. Our high-performance shoe adhesive hardened rapidly within 15 minutes of application. After the shoe was worn, performance measurement was carried out by walking and contact with hard objects. These test conditions were conducted under conditions covering 48 hours. Our study, which sheds light on shoe manufacturers regarding adhesives, provides ideal properties.     References [1]https://bilimkultur.com/yapistirici-cesitleri-yapistirici nedir/#Yapistirici_Cesitleri_Nelerdir [2]https://acikders.ankara.edu.tr/pluginfile.php/74929/mod_resource/content/1/Unite_4.pdf [3]https://www.sportiveturkiye.com/dogru-giyin/su-gecirmez-ayakkabilarin-ozellikleri/ [4]Cheramie, H. S., & O'Grady, S. E. (2003). Hoof repair and glue-on shoe adhesive technology. Veterinary Clinics: Equine Practice, 19(2), 519-530. [5]Bulus, G. S., & Bulus, E. (2021). Production of Aerogel-Silica Based Super Hydrophobic Waterproof Material in Smart Surface Coatings. JOURNAL OF MATERIALS AND ELECTRONIC DEVICES, 7(1), 15-18.     Lecturer Erdi Buluş Metallurgy and Materials Engineer / Senior Materials Technology Specialist Istanbul Arel University ArelPOTKAM (Polymer Technologies and Composite Application and Research Centre)   Gülseren Sakarya Buluş Specialist Nurse Istanbul Provincial Health Directorate / Health Services Headquarters Bahçeşehir University / Engineering Management Thesis Master's Program   Kübra Gödek Istanbul Arel University Biomedical Engineering   Assistant Professor / Prof. Dr. Tayfun Çetin Hakkari University Department of Electrical and Energy Natural Gas and Plumbing Technology