Effect of Artificial Acid Rain on Aluminium Tanned Leather

Abstract

EFFECT OF ARTIFICIAL ACID RAIN ON ALUMINIUM TANNED LEATHERABSTRACT. This article aims at studying the influence of gaseous pollutants on aluminium tanned leather. Artificial acid rain was used to soak the aluminium tanned collagen materials for 0, 4, 8, 12 and 16 days, then some analytical techniques were used to evaluate the changes of leather during the aging process. Micro hot table (MHT), differential scanning calorimetry (DSC) and thermogravimetry (TG) were used to evaluate the influence of artificial acid rain on thermal behaviors. Scanning electron microscope(SEM) was used to investigate the changes of fibrous morphology during aging process. Fourier transform infrared spectroscopy (FT-IR) was used to investigate the changes of structural property after artificial acid rain treatment. With the extension of aging time, thermal stability and heat resistance were gradually reduced, including shrinkage temperature, thermal denaturing temperature, associated enthalpy, weight loss and temperature for maximum decomposition rate. SEM images showed that the collagen fibers were greatly damaged, the gaps among fibres were disappeared and the fibre bundles were randomly ruptured with the aging time. The FT-IR results showed that, during the aging process, amide A band was moved to higher numbers, amide I and amide II band of collagen were gradually shifted to lower numbers. Consequently, the structure and performance of aluminium tanned leather were damaged by artificial acid rain and the longer the aging time is, the greater the damage is. KEY WORDS: leather making; aluminium tanned leather; artificial acid rain; aging INFLUENTA PLOII ACIDE ARTIFICIALE ASUPRA PIELII TABACITE CU ALUMINIU REZUMAT. Obiectivul acestui articol este acela de a studia influenta poluantilor gazosi asupra pielii tabacite cu aluminiu. S-a utilizat ploaia acida artificiala pentru a înmuia materialul colagenic tabacit cu aluminiu timp de 0, 4, 8, 12 si 16 zile, apoi s-au efectuat anumite analize pentru a evalua modificarile pielii în timpul procesului de îmbatrânire. S-au utilizat tehnicile Micro Hot Table (MHT), calorimetria cu scanare diferentiala (DSC) si termogravimetria (TG) pentru a evalua influenta ploii acide artificiale asupra comportamentului termic. Microscopia electronica de baleiaj (SEM) a fost utilizata pentru a investiga modificarile morfologiei fibroase în timpul procesului de îmbatrânire. Spectroscopia în infrarosu cu transformata Fourier (FT-IR) a fost utilizata pentru a investiga modificarile proprietatilor structurale dupa tratamentul cu ploaie acida artificiala. Odata cu prelungirea timpului de îmbatrânire, stabilitatea termica si rezistenta la caldura s-au redus treptat, inclusiv temperatura de contractie, temperatura de denaturare termica, entalpia asociata, pierderea în greutate si temperatura ratei maxime de descompunere. Imaginile SEM au aratat ca fibrele de colagen au fost foarte deteriorate, golurile dintre fibre au disparut, iar fasciculele de fibre s-au rupt în mod aleatoriu, odata cu prelungirea timpului de îmbat...

Effect of UV Irradiation on Vegetable Tanned Leather

“…Pielea tãbãcitã vegetal a fost tratatã în camera QUV (T 2 = 50°C, iradiere = 1.77 W/mm nm, ë = 340 nm) timp UVA de 0, 30, 60, 90, 120 ºi 150 ore. S-au utilizat câteva tehnici analitice pentru a evalua modificãrile pielii în timpul procesului de îmbãtrânire: s-au efectuat analizele DSC, TG ºi MHT pentru a evalua variaþia comportamentului termic; rezistenþa la rupere, rezistenþa la sfâºiere ºi alungirea la rupere au fost analizate pentru a evidenþia deteriorarea proprietãþilor mecanice; analiza FT-IR ºi microscopia opticã au fost folosite pentru a investiga modificãrile proprietãþilor structurale ºi histologice [8][9][10].…”

“…Some analytical techniques were used to evaluate the changes of leather during the aging process: DSC, TG and MHT were used to evaluate the variation of their thermal behaviors; tensile strength, tear strength and elongation at break were analyzed to show the damages of mechanical properties; FT-IR and optical microscopy were used to investigate the changes of structural and histological properties [8][9][10].…”