scholarly journals Highly Accelerated Aging Method for Poly(ethylene terephthalate) Film Using Xenon Lamp with Heating System

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Masahiro Funabashi ◽  
Fumi Ninomiya ◽  
Akihiro Oishi ◽  
Akihiko Ouchi ◽  
Hideaki Hagihara ◽  
...  
Keyword(s):  
Light Intensity ◽  
Degradation Products ◽  
Heating Temperature ◽  
Irradiation Time ◽  
Xenon Lamp ◽  
Eyring Model ◽  
Xenon Light ◽  
Pet Film ◽  
Conventional Systems ◽  
Pet Films

PET films were degraded at temperature higher than 100°C with steam and xenon light by using the newly developed system. Degradation products obtained using the proposed and conventional systems were essentially the same, as indicated by the similar increase in the intensity of the carbonyl peak near 1685 cm−1 in the FT-IR spectra of irradiated specimens and spectrum of original PET film. Elastic moduli derived from the stress-strain (SS) curves obtained in tensile tests were almost the same in the case of the proposed and conventional systems and were independent of the heating temperature, light intensity, and irradiation time. Tensile strength of degraded PET films decreases with increasing heating temperature. Tensile strengths of PET films degraded at same temperature decrease linearly with increasing intensity of xenon light. The lifetime at 90% strength of PET films was calculated. Attempts were made to express this lifetime as functions of the light intensity and the reciprocal of the absolute temperature by using the Eyring model. Estimated lifetime 15.9 h of tensile test using Eyring model for PET film agreed with the lifetime 22.7 h derived from data measured using the xenon weather meter.

scholarly journals Effect of light intensity and irradiation time on the polymerization process of a dental composite resin

2004 ◽  
Vol 7 (2) ◽  
pp. 313-318 ◽  
Author(s):  
José Augusto César Discacciati ◽  
Alisson Discacciati Neves ◽  
Rodrigo Lambert Oréfice ◽  
Flávio Juliano Garcia Santos Pimenta ◽  
Herbert Haueisen Sander
Keyword(s):  
Light Intensity ◽  
Composite Resin ◽  
Irradiation Time ◽  
Dental Composite ◽  
Polymerization Process ◽  
Dental Composite Resin ◽  
Effect Of Light

Influence of Temperature and Relative Humidity on Perm-Selectivity of PET Packaging Film

2011 ◽  
Vol 295-297 ◽  
pp. 1206-1210
Author(s):  
Yan Feng Guo ◽  
Xian Ping Ma ◽  
Yu Yan ◽  
Yun Gang Fu
Keyword(s):  
Water Vapor ◽  
Relative Humidity ◽  
Experimental Studies ◽  
Thermodynamic Temperature ◽  
Packaging Film ◽  
Influence Of Temperature ◽  
Carbon Dioxide Gas ◽  
Pet Film ◽  
Pet Films ◽  
Temperature Water

The main feature of this article is the investigation on the influence of temperature, relative humidity, film thickness on permeability of PET packaging film, the analysis of perm-selectivity of the packaging films for oxygen gas and carbon dioxide gas, and the evaluation on experimental formulas of water vapor, O2 and CO2 gas permeating rates on the basis of gas molecular osmotic reaction kinetics and regression analysis. The comparison between experimental studies and calculation indicates that: (1) with increment of ambient temperature water vapor, O2 and CO2 permeating rate of PET films and PET/Al film also rise, and the logarithm of water vapor, O2 and CO2 gas permeating rates has linear relation with the reciprocal of thermodynamic temperature, and (2) the influence of relative humidity on water vapor permeating rate of PET film with thickness 12µm is the least, and that of PET film with thickness 20µm and PET/Al film with thickness 18µm is a little obvious. (3) The PET films hold remarkable perm-selectivity for O2 and CO2 gas, and CO2 gas permeating rate is about two times of O2 gas, yet O2 and CO2 gas permeating rates of PET/Al film are both very low and have small difference, so the PET/Al film has better barrier performance than the PET film.

UV Based Advanced Oxidation Process for Degradation of Ciprofloxacin: Reaction Kinetics, Effects of Interfering Substances and Degradation Product Identification

2021 ◽  
Author(s):  
Bijoli Mondal ◽  
Shib Sankar Basak ◽  
Arnab Das ◽  
Sananda Sarkar ◽  
Asok Adak
Keyword(s):  
Organic Compounds ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
Uv Light ◽  
Degradation Products ◽  
Irradiation Time ◽  
Advanced Oxidation ◽  
Quantum Yields ◽  
Photon Flux ◽  
First Order

Abstract In the photochemical UV-H2O2 advanced oxidation process, H2O2 absorbs UV light and is decomposed to form hydroxyl radicals (OH·), which are highly excited and reactive for electron-rich organic compounds and hence can degrade organic compounds. In the present work, the UV-H2O2 process was investigated to degrade ciprofloxacin (CIP), one of India's widely used antibiotics, from aqueous solutions using a batch type UV reactor having photon flux = 1.9 (± 0.1) ×10-4 Einstein L-1 min-1. The effects of UV irradiation time on CIP degradation were investigated for both UV and UV-H2O2 processes. It was found that about 75% degradation of CIP was achieved within 60 s with initial CIP concentration and peroxide concentration of 10 mg L-1 and 1 mol H2O2/ mol CIP, respectively, at pH of 7(±0.1) and fluence dose of 113 mJ cm-2. The experimental data were analyzed by the first-order kinetics model to find out the time- and fluence-based degradation rate constants. Under optimized experimental conditions (initial CIP concentration, pH and H2O2 dose of 10 mg L-1, 7(±0.1) and 1.0 mol H2O2 / mol CIP, respectively), the fluence-based pseudo-first-order rate constant for the UV and UV-H2O2 processes were determined to be 1.28(±0.0) ×10-4 and 1.20(±0.04) ×10-2 cm2 mJ-1 respectively. The quantum yields at various pH under direct UV were calculated. The impacts of different process parameters such as H2O2 concentration, solution pH, initial CIP concentration, and wastewater matrix on CIP degradation were also investigated in detail. CIP degradation was favorable in acidic conditions. Six degradation products of CIP were identified. Results clearly showed the potentiality of the UV-H2O2 process for the degradation of antibiotics in wastewater.

scholarly journals Estimasi Produk Degradasi Ekstrak Kasar Pigmen Alga Merah Kappaphycus alvarezii (Doty) Doty Varian Merah, Coklat, dan Hijau: Telaah Perbedaan Spektrum Serapan

2012 ◽  
Vol 17 (1) ◽  
pp. 31
Author(s):  
Helly De Fretes ◽  
A.B. Susanto ◽  
Budi Prasetyo ◽  
Heriyanto Heriyanto ◽  
Tatas H.P. Brotosudarmo ◽  
...  
Keyword(s):  
Light Intensity ◽  
Absorption Spectra ◽  
Degradation Products ◽  
Kappaphycus Alvarezii ◽  
Red Alga ◽  
Before And After ◽  
Heating Treatment ◽  
Pigment Extract ◽  
The Difference ◽  
Difference Absorption

Penelitian ini bertujuan untuk mengestimasi produk degradasi pigmen ekstrak kasar alga merah Kappaphycus alvarezii (Doty) Doty varian merah, coklat dan hijau yang terbentuk selama perlakuan iradiasi dan pemanasan, melalui perbedaan spektrum serapannya. Ketiga varian diekstraksi menggunakan 100% metanol. Uji fotostabilitas ekstrak pigmen dilakukan dengan iradiasi menggunakan lampu Volpi intralux 4100 pada intensitas cahaya 39300 lux, 56700 lux dan 76400 lux.  Lama waktu penyinaran 0, 5, 10, 15, dan 20 menit. Sedangkan uji termostabilitas  dilakukan pada suhu 25 dan 90 ° C selama 0, 3, 6 24, dan 48 jam. Pola spektra diukur pada panjang gelombang 300-800 nm sebelum dan sesudah perlakuan dengan spektrofotometer UV-Tampak Shimadzu 1700. Data dianalisis dengan SPINA Versi 3, untuk memperoleh intensitas maksimum dan perbedaan spektra serapan. Hasil penelitian menunjukkan bahwa produk degradasi pigmen ekstrak kasar alga merah K. alvarezii dapat diidentifikasi melalui spektrum serapan dan hasil perbedaan spektra serapan. Isomer cis karotenoid, karotenoid tidak berwarna, dan feofitin a diestimasi sebagai produk degradasi yang terbentuk selama perlakuan iradiasi dengan intensitas cahaya 76400 lux dan perlakuan pemanasan pada suhu 90°C selama 48 jam. Penurunan intensitas warna larutan pigmen juga mengindikasikan terbentuknya produk degradasi selama perlakuan. Kata kunci: Kappaphycus alvarezii, perbedaan spektrum serapan, produk degradasi The aims of this study were to estimate the degradation products of crude pigment extracts from red, brown, and green varieties of red alga Kappaphycus alverezii (Doty) Doty that formed during irradiation and heating treatment from their difference absorption spectra. All three variants were extracted using 100% methanol. The photostability assay of crude pigment extracts was conducted by irradiating the crude pigment extracts with a day light lamp (Volpi, Intralux 4100) at 39300 lux, 56700 lux and 76400 lux light intensity during 0, 5, 10, 15, and 20 minutes treatment, whereas the thermostability assay was performed at 25 and 90 °C for 0, 3, 6 24, and 48 hours. The absorption spectra of the crude pigment extract before and after each treatment were monitored successively at 300-800 nm using MultiSpec 1501 UV-VIS spectrophotometer. Data were analyzed with spina Version 3, to obtain maximum intensity and the difference absorption spectra. The results showed that the  degradation products of crude pigment extracts from red alga K. alvarezii could be identified by absorption spectra and difference absorption spectra. Cis isomers carotenoids, colorless carotenoids, and feofitin-a were estimated as degradation product formed during the irradiation treatment with 76400 lux of light intensity and heating treatment at a temperature of 90 ° C for 48 hours. Decrease in the intensity of the color of pigment solution also indicates the formation of degradation products during treatment.Key words: Kappaphycus alvarezii, difference absorption spectra, degradation products

scholarly journals ADHESION OF PET/PSMA INTERFACES REINFORCED WITH PLASMA TREATMENT

2006 ◽  
Vol 13 (02n03) ◽  
pp. 265-271
Author(s):  
CHI-AN DAI ◽  
TAI-AN TSUI ◽  
YAO-YI CHENG
Keyword(s):  
Fracture Toughness ◽  
Plasma Treatment ◽  
Fracture Energy ◽  
Functional Groups ◽  
Surface Composition ◽  
Treatment Time ◽  
Bulk Material ◽  
Plasma Treatment Time ◽  
Pet Film ◽  
Pet Films

The interface between biaxially oriented poly (ethylene terephthalate) (PET) films and poly (styrene-co-maleic anhydride) (PSMA) was reinforced by nitrogen plasma treatment of PET film and subsequent annealing treatment of the PET/PSMA bi-material. The fracture toughness, Gc, of the interface was quantitatively measured using an asymmetric double cantilever beam test (ADCB). X-ray photoelectron spectrometry (XPS) was used to measure the change in the surface composition of PET films upon plasma treatment and correlate the fracture toughness of the interface. The fracture energy of PET/PSMA interface is significantly enhanced by annealing the plasma treated PET with PSMA at a temperature greater than the glass transition temperature of PSMA (~ 120°C). At an annealing temperature of 150°C, Gc increases with increasing plasma treatment time and reaches a plateau value of ~ 100–120 J/m2, a two order of magnitude increase in Gc compared with that of samples annealed at 130°C. The enhancement of the adhesion is resulted from the in-situ formation of copolymers due to reaction between amine functional groups from the plasma treatment and anhydride groups from PSMA. For plasma treatment time < 10 s, scanning electron microscope (SEM) measurement show that the fracture surface is relatively smooth indicating an interfacial failure between PET/PSMA. With increasing plasma treatment time and therefore increasing the amount of nitrogen functional groups on PET surface, large plastic deformation takes place at the PET/PSMA interface. For treatment time ≥ 100–150 s, the PET/PSMA interface becomes stronger than PET bulk material and consequently crack deviates from the interface and the failure occurs within the PET film. The interlayer fracture energy of a biaxially oriented PET film can thus be quantitatively measured with a Gc value of roughly 120 J/m2.

COLORATION OF POLYETHYLENE TEREPHTHALATE (PET) FILM BY 3MeV PROTON BEAMS

2001 ◽  
Vol 11 (03n04) ◽  
pp. 93-101 ◽  
Author(s):  
S. Matsuyama ◽  
K. Ishii ◽  
H. Yamazaki ◽  
H. Endoh ◽  
H. Yuki ◽  
...  
Keyword(s):  
Polyethylene Terephthalate ◽  
Color Centers ◽  
Sequential Process ◽  
Proton Beams ◽  
Spin Resonance ◽  
Ft Ir ◽  
Absorbance Changes ◽  
Pet Film ◽  
Pet Films ◽  
Ft Ir Spectroscopy

Coloration of polyethylene terephthalate (PET) films by using 3 MeV proton beams was studied by means of absorption spectroscopy, electron spin resonance (ESR) spectroscopy and Fourier transform infrared absorption (FT-IR) spectroscopy. Absorbance of the films increased with the dose and faded in time. Absorbance changes are caused by formation of color centers. The color centers had three components: permanent, long-lived and short-lived. Long-lived and short-lived color centers were formed by reactive species such as radicals. Annealing of color center is well explained by a proposed sequential process.

scholarly journals Heating Characteristics of Film Prepared with Polymer Composites Containing Graphite

2018 ◽  
Author(s):  
Seojin Kim ◽  
Weontae Oh ◽  
Jong-Seong Bae ◽  
Jeong Hyun Yeum ◽  
Jaehyung Park ◽  
...  
Keyword(s):  
Thermal Imaging ◽  
Chemical Structure ◽  
Heating Temperature ◽  
Infrared Thermal Imaging ◽  
Dc Voltage ◽  
Copper Electrodes ◽  
Physical Chemical ◽  
Imaging Camera ◽  
Pet Film ◽  
The Relationship

Heating films were prepared by using poly(methyl methacrylate) and polybutadiene composites containing graphite. The heating film was prepared by casting the as-made polymer composite on PET film. Copper electrodes were attached to both ends of the as-prepared film, and the heating characteristics of the film was analyzed while applying DC voltage. The electrical conductivity and the heating temperature of the heating films depended on the size, the structure, the content and the dispersion characteristics of the graphite in the composite. The electrical resistance of the heating film was controlled to adjust the heating temperature of the film. The relationship between the physical/chemical structure and the heating characteristics of the composite film was studied by measuring the heating temperature as functions of film thickness and resistance by using an infrared thermal imaging camera. The lower the film resistance, the higher the heating temperature of the film. The surface temperature was uniform throughout the film.

Effects of sterically hindered N-alkoxyamines on photooxidative stability of reinforced polypropylene

e-Polymers ◽  
2012 ◽  
Vol 12 (1) ◽  
Author(s):  
Daniela Enescu ◽  
Alberto Frache
Keyword(s):  
Degradation Products ◽  
Irradiation Time ◽  
Linear Part ◽  
Oxidative Degradation ◽  
Polymer Degradation ◽  
Nitroxide Radical ◽  
Degradation Process ◽  
Peroxy Radicals ◽  
Absorption Bands ◽  
Sterically Hindered

AbstractIn the present paper the influence of Flamestab® NORTM 116 (abbrev. FNOR), a sterically hindered N-alkoxyamine stabilizer, on the photo-oxidative stability of calcium carbonate reinforced polypropylene (abbrev. CCPP) used for production of plastic collars has been investigated. The samples, prepared by melt compounding, were exposed to artificial accelerated photo-ageing carried out at λ>300 nm and 45 °C in air. FT-IR and UV-VIS analysis revealed that the deterioration of neat CCPP takes place very rapidly in comparison with the composites containing FNOR. Hydroperoxides and various carbonyl species are formed as the main degradation products during the photo-oxidation process. Moreover, the intensity of the absorption bands grows with increasing of UV exposure time indicating that the material suffers a photo-oxidative degradation process. Indeed, addition of only 0.1 wt.-% FNOR did not significantly modify the length of the induction period of neat CCPP, but a strong efficiency was obtained by increasing the amount of FNOR (0.5 wt.-%) which shows an increase of eight times more as compared with neat CCPP. Therefore, it may be supposed that OIT is linked to the level of concentration of the stabilizer. This remarkable increase in composite stability demonstrated by a lengthening of OIT is typical for sterically hindered N-alkoxyamine stabilizers since they are very efficient at scavenging freeradicals formed as the polymer degrades. In other words, these UV stabilizers are converted to nitroxide radicals (see Scheme 1) which readily trap the polymer degradation species to produce alkoxyamines. Then, the formed alkoxyamines do subsequently react with peroxy radicals to regenerate the active nitroxide radical, thereby this process (called Denisov cycle) proceed in a regenerative cycle, thus retarding oxidative polymer degradation. The increase of absorbance in the carbonyl region as a function of irradiation time was used to determinate the photooxidation rate. It was found out that the photooxidation rate measured from the slope of linear part of the curves is significantly decreased for the CCPP/FNOR 0.5 composite compared to neat CCPP. In the light of the above mentioned findings, FNOR could be taken into consideration as an UV stabilizer for CCPP.

Characteristics of Corona-Charged PET Sandwich Electrets

2005 ◽  
Vol 480-481 ◽  
pp. 123-128 ◽  
Author(s):  
L.S. Tai ◽  
Y.W. Wong ◽  
Y.M. Poon ◽  
F.G. Shin
Keyword(s):  
Thermal Relaxation ◽  
Charge Injection ◽  
Relaxation Processes ◽  
Surface Charges ◽  
Depolarization Current ◽  
Charge Effects ◽  
Long Time ◽  
Pet Film ◽  
The Individual ◽  
Pet Films

Polyethylene terephthalate (PET) is one of the major electret materials which has been studied and widely used in charge storage applications for a long time. The homo-charge and hetero-charge formation responsible for the electret effect of PET can be explained by the dipolar polarization, space charge separation and charge injection respectively as a result of contact poling or corona charging. These processes are also verifiable from studies of surface charges and thermally stimulated depolarization current (TSDC) of the PET films. Now consider a stack of PET films charged under the same condition as a single film. It would be intuitively expected that the electret effects of the individual films of the stack should be different due to their different positions in the stack. However, in a recent study on charged PET stacks, it was found that the electret effects of the individual films are quite similar. The surface charges of the individual films are about the same and they sum to make same total as a single charged PET film. On the other hand, the TSDC thermograms of individual films show similar characteristics in the thermal relaxation processes where homo- and hetero- charge effects are still observed. From the TSDC results, especially for the film in the middle of a triple layer sandwich, it shows clearly dipolar polarization and charge injection related peaks. These findings agree with the results of surface charge studies of the individual films.

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