Razvoj modela za napovedovanje ultravijoličnih zaščitnih lastnosti tkanin

Kostajnšek, Klara (author), Dimitrovski, Krste (mentor), Urbas, Raša (comentor)

Namen doktorske disertacije je bil razviti hitro in učinkovito metodo za napovedovanje zaščitnih lastnosti tkanin pred UV sevanjem že v fazi njihovega načrtovanja oz. projektiranja. Z definiranjem koeficientov prepustnosti (T), odboja (R) in absorpcije (A) ultravijoličnega (UV) sevanja na podlagi razširjene teorije faktorja kritja tkanin je bil namen postaviti nov matematični model za napovedovanje zaščitnih lastnosti tkanin pred UV sevanjem. Raziskava je temeljila na razvoju in razširitvi teorije faktorja kritja, kjer se je s pomočjo monofilamentnih poliestrnih tkanin postavil matematični model za ugotavljanje zaščitnih lastnosti tkanin pred UV sevanjem. Uporabnost omenjenega modela smo potrdili s primerjavo in ugotavljanjem stopnje ujemanja med teoretičnimi vrednostmi, izračunanimi po postavljenemu modelu, in izmerjenimi vrednostmi parametrov UV sevanja. Z visokim ujemanjem (r > 0,98), majhno razliko med omenjenimi vrednostmi ter s potrditvijo teoretične predpostavke, kjer velja, da koeficient prepustnosti UV sevanja skozi del tkanine, pokrit z dvema nitma (K2T), predstavlja kvadrat koeficienta prepustnosti UV sevanja skozi delež tkanine, pokrit z eno nitjo (K1T2), ter koeficient absorpcije UV sevanja skozi delež tkanine, pokrit z dvema nitma (K2A), predstavlja kvadratni koren koeficienta absorpcije skozi delež tkanine, pokrit z eno nitjo (??K?_1A), se je uporabnost postavljenega matematičnega modela z gotovostjo potrdila. Razvili smo tudi novo metodo določanja maksimalne gostote, ki temelji na razširjeni teoriji faktorja kritja. Ta metoda je bila uporabljena za določitev konstrukcijskih parametrov in parametrov UV sevanja, katerih poznavanje je nujno za uporabo modela. V namen širše uporabe matematičnega modela sta bili izdelani seriji enoplastnih in dvoplastnih vzorcev sistemov niti iz enobarvnih surovih poliestrnih (PES) rotorskih prej in obarvanih bombažnih (CO) prstanskih prej v dveh različnih dolžinskih masah. Razvita je bila metoda priprave vzorcev enoplastnih in dvoplastnih nitnih sistemov z enakomerno gostoto niti po površini. V I. sklopu raziskav so se vzorci iz PES preje razlikovali le v št. zavojev preje in gostoti niti, v II. sklopu raziskav pa v barvi in gostoti CO niti. Vrednosti odprte površine in premerov preje se je določilo z uporabo slikovne analize. Visoka stopnja ujemanja med teoretičnimi in merjenimi vrednostmi (r > 0,94), majhne razlike med vrednostmi ter potrditev postavljene teorije dokazujejo uspešno uporabnost postavljenega matematičnega modela. Slednje podaja možnost praktične uporabe predvsem za namen izdelave zaščitnih oblačil.

• Language: Slovenian
• Keywords: UV sevanje, zaščitne lastnosti tkanin, matematični model za napovedovanje zaščitnih lastnosti pred UV sevanjem, faktor kritja, tkanine
• Work type: Doctoral dissertation
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Year: 2019
• PID: 20.500.12556/RUL-112999
• Publication date in RUL: 28.11.2019

Secondary language

• Language: English
• Title: Development of model for predicting ultraviolet protective properties of woven fabrics

Abstract

The aim of the doctoral dissertation was to develop a fast and efficient method for predicting the UV protective properties of fabrics already in the stage of planning and designing. We established a mathematical model to calculate and predict the UV-protective properties of fabrics, using transmittance (KT), reflection (KR) and absorption (KA) coefficients of ultraviolet (UV) radiation. The model is based on our extended cover factor theory by using the geometrical properties of monofilament polyester fabrics. The model was first validated on monofilament polyester fabrics by comparing the theoretical values calculated according to the model with previously measured values of the UV radiation parameters. The results show high correlations (r > 0.98) and small differences between the theoretical and measured values, indicating the high model efficiency. Moreover, the results confirm the theoretical assumption that the coefficient of UV transmission of the fabric area covered with two yarns (K2T) is approximately equal to the power function of the coefficient of UV transmission of the fabric area covered with one yarn (K1T2), and that the coefficient of UV absorption of the fabric area covered with two yarns (K2A) is approximately equal to the square root of the coefficient of UV absorption of the fabric area covered with one yarn (〖⠚K〗_1A). Apart from developing a new model, we also defined a new method to determine maximum density, which is also based on the extended version of the cover factor theory. This method was used to determine the constructional parameters and parameters of UV radiations that are necessary for using the model. For its broader use, the model was also validated on a series of single- and double-layer thread systems, using uncoloured raw polyester (PES) rotor yarn and coloured cotton (CO) ring yarns in two different counts. For that purpose, the method for preparing single-layer or double-layered thread systems with uniform density was developed. PES samples differed in the number of twist yarn and thread density, while CO samples differed in colour and density of the thread. Open area and yarn diameters were determined using image analysis. In both cases, the results show high correlations (r > 0.94), small differences between theoretical and measured values, and confirm the aforementioned theoretical assumption. Taken together, the results clearly show high efficiency of our model and practical importance, since it can be used to develop and produce protective clothing.

• Keywords: UV radiation, protective properties of fabrics, mathematical model for the prediction of protective properties against UV radiation, coverage factor, fabric