Preparation and Water Resistance of the New Water Epellent Agent of Paper Lunch Boxes

2011 ◽  
Vol 236-238 ◽  
pp. 1199-1202
Author(s):  
Shu Fang Zhou ◽  
Chuan Shan Zhao ◽  
Jing Jing Wang

In this paper, a kind of sizing synergist,AKD,cationic rosin(CRS) and oil resistance agent were mixed in different proportions, we make it as a kind of new water repellent agent ,and for internal sizing. The best dosage and the composite ratio of the synergist, AKD, cationic rosin and oil resistance agent was discussed mainly in this experiment. And then the copy paper were tested of the substanceweight and contact angle, and compared with the water resistance when the domestic water repellent agent or AKD was added alone. Conclusions of this experiment are following: the optimal conditions were that the mass ratio of AKD and CRS is 6:4, the additive level of AKD and the cationic rosin is 6% (based on dry weight of pulp), the quantity of the sizing synergist is 0.5% , and no oil resistance agent was added, the effect of water resistance is best.

2018 ◽  
Vol 89 (6) ◽  
pp. 1013-1026 ◽  
Author(s):  
Rongrong Yu ◽  
Mingwei Tian ◽  
Lijun Qu ◽  
Shifeng Zhu ◽  
Jianhua Ran ◽  
...  

Cotton fabrics with hydrophilic-to-hydrophobic asymmetric surfaces are attractive as potential utilizable structures for functional garments. The spray-coating route could be deemed as a fast and simple way to achieve asymmetric surfaces. In this paper, SiO2 nanoparticles with size ∼ 205 nm were synthesized via the modified sol-gel method, and then modified with poly(vinylidene fluoride) (PVDF) to form a hydrophobic surface. The SiO2 nanoparticles modified with PVDF were uniformly deposited on the outer surface of cotton fabric aided with the robust air flow force from the sprayer. The morphology and chemical structures were characterized by scanning electron microscopy, mapping, atomic force microscopy, X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy. The results indicated that SiO2 nanoparticles were evenly deposited on the surface of cotton fibers and stable interfacial interaction occurred between SiO2 and PVDF molecular chains. The existence of SiO2 could increase the roughness of the fabric surface, which could enhance the water-repellent property of the coated fabrics. Furthermore, the water-repellent property and thermal insulation properties were evaluated via the water contact angle and thermal conductivity tests, respectively, and the results showed that 20 wt.% SiO2/PVDF fabric achieved a desirable level of contact angle, 136.6°, which was the largest water contact angle among all the samples, and the lowest thermal conductivity of 0.033 W/mK, resulting from the existence of SiO2 nanoparticles. Such a fast and simple spray-coating strategy could be widely introduced into asymmetric fabric modification, and such asymmetric fabrics with reasonable water-repellent and thermal insulating outer surfaces could act as candidates in the field of functional garments.


2015 ◽  
Vol 1112 ◽  
pp. 359-362
Author(s):  
Aisyah Nor Hasnan ◽  
Azizah Hanom Ahmad

Dammar plant resin is a local natural resin that can be bled from Dipterocaupacea sp of tree. It can be found abundantly in Malaysia’s tropical forest especially in Sarawak. Dammar and Titanium Dioxide was mixed in a various wt% to produce Dammar-modified Titanium Dioxide coating system. The modified coating systems were then spin-coated onto Aluminium Q-panel as the substrate. Coated Q-panels were left to cure at room temperature. The curing time was evaluated using dust free stage. The addition of Titanium Dioxide into the coating system fastens the curing time taken for the coated Q-panel to be cure. It only took about 11-12 minutes to dry compared to the coating system before the addition of Titanium Dioxide where a quite long duration required, 32 minutes. Contact angle measurement was also carried out in order to determine the wettability of the coating system. The surface coated with dammar-modified titanium dioxide found to be hydrophobic where a quite large contact angle obtained for the sample with 3 wt% of Titanium Dioxide (PDT3). The water droplets actually rest on the coating surface without wetting the surface. Water absorption test was done to strengthen the contact angle results where coated substrate was soaked into distilled water for 24 hours and being weighed before and after soaking. The difference of before and after soaking weigh showed that the coating surface does not absorb that much water where only approximately 0.02% of water being absorbed by the coating system for 3 wt%. It proved that the coating systems applied are hydrophobic.


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 4003
Author(s):  
Seongyong Kim ◽  
Minho Jo ◽  
Jongsu Lee ◽  
Changwoo Lee

Solar cells are important alternatives to fossil fuels for energy generation in today’s world, where the demand for alternative, renewable sources of energy is increasing. However, solar cells, which are installed outdoors, are susceptible to pollution by environmental factors. A solution to overcome this limitation involves coating solar cell surfaces with functional coatings. In this study, we propose a transmittance control method for a tensioned web in a roll-to-roll, transparent, water-repellent film coating. First, we analyzed the effects of process conditions on the transmittance and contact angle of the transparent water-repellent film during roll-to-roll slot-die coating. It was confirmed that the tension was the most dominant factor, followed by the coating gap. Through the tension control, the transmittance was changed by 3.27%, and the contact angle of the DI water was changed by 17.7°. In addition, it was confirmed that the transmittance was changed by 0.8% and the contact angle of DI water by 3.9° via the coating gap control. Based on these results, a transmittance prediction model was developed according to the tension and coating gap, and was then verified experimentally. Finally, a water-repellent film with a high transmittance of 89.77% was obtained using this model.


2020 ◽  
Vol 10 (4) ◽  
pp. 159
Author(s):  
. EMMYZAR

<p>Tanaman nilam tumbuh dan berproduksi dengan baik pada daerah dengan curah hujan relatif tinggi dan merata sepanjang tahun. Tanaman dalam kondisi kekurangan air terus menerus akan mengalami strcs air dan berpengaruh terhadap proses fisiologis, menurunkan permukaan trans- pirasi, luas daun menurun, dan mempercepat dcfiidrasi protoplasma. Penelitian pengaruh ketersediaan air terhadap petumbuhan dan produksi 2 (dua) klon nilam dilakukan di rumah kaca Instalasi Penelitian Cimanggu, Balittro Bogor mulai bulan Nopember 1999 sampai dengan Mei 2000. Penelitian ini betujuan untuk mengetahui pengaruh ketersediaan air terhadap partumbuhan dan produksi dua klon nilam (klon Sidikalang dan klon Situak) sekaligus diamati pengaruhnya terhadap kadar dan kualitas minyak nilam (rendemen, warna dan kandungan patchouly alkohol). Percobaan dilakukan dalam polibag menggunakan tanah kering jenis latosol Cimanggu Bogor yang diaduk dengan pupuk kandang sapi (3:1) sebanyak 10 kg/polibag disusun menggunakan rancangan factorial (dua faktor) dalam rancangan acak lengkap (RAL), diulang 3 kali. Ukuran plot 8 polibag/ perlakuan. Faktor pertama : klon nilam terdiri dari 2 jenis (K) yaitu : Kl = klon Sidikalang dan K2 = klon Situak. Faktor kedua: tingkat ketersediaan air (A) 4 taraf yaitu Al = 25% kapasitas lapang, A2 = 50% kapasitas lapang, A3 = 75% kapasitas lapang, dan A4 = 100 % kapasitas lapang. Peubah yang diamati meliputi persentase tumbuh tunas, tinggi tanaman, luas daun, bobot daun basah dan bobot daun kering, kadar minyak digambarkan dari rendemen dan kualitas minyak (wana dan kandungan patchouly alkohol). Hasil penelitian menunjukkan bahwa untuk jumlah tunas tidak ada interaksi antara tingkat ketersediaan air dan klon yang diuji, tetapi untuk jumlah daun ada interaksi. Tingkat pemberian air 75% kapasitas lapang (KL) secara keseluruhan memberikan pertumbuhan optimum bagi kedua klon, kecuali untuk parameter jumlah daun. Pada klon Situak. tingkat pemberian air 100% KL yang memberikan jumlah daun terbanyak. Perlakuan ketersediaan air 100% KL pada klon Sidikalang memberikan bobot daun kering tetinggi dibanding perlakuan lainnya, sedang untuk klon Situak, ketersediaan air pada taraf 75% KL memberikan bobot daun kering tetinggi. Rendemen minyak klon Situak dengan tingkat ketersediaan air 25% KL tertinggi (4.0%) dengan wana minyak kuning muda tcrang, diikuti tingkat 50% KL (3.0%) dengan wana minyak kusam/kemh. Kandungan patchouly alkohol klon Situak rata-rata (30%) lebih baik daripada klon Sidikalang, diperoleh dari perlakuan ketersediaan air 25% KL. Dapat disimpulkan bahwa untuk memperoleh petumbuhan dan produksi yang tinggi, ketersediaan air dalam tanah diperlukan antara 75 - 100% KL. Namun, untuk mendapatkan kandungan patchouly alkohol tinggi ketersediaan air yang dibutuhkan lebih rendah yaitu 25 % - 50%) KL.</p><p>Kata kunci: Nilam, Pogostemon cablin, ketersediaan air, petumbuhan, produksi</p><p> </p><p><strong>ABSTRACT</strong></p><p><strong>The effect of water availability the growth and production of two patchouly clones </strong></p><p>Patchouly plant grows and produces very well in the area with high and everly rain fall through the year. Plants with continuous shortage of water would face water stress and affect physiologis process, transpiration surface, leaf area and protoplasmic dehydration. Several levels of water needs were tested in this experiment, which was carried out in a glass house of Cimanggu Installation, Indonesian Spice and Medicinal Crops Research Institute, Bogor, rom November 1999 to May 2000. The objective was to find out the effect of water availability on two clones of patchouly growth, production and oil content (rendement, colour and patchouly alcohol). The experiment was conducted in polybags using Cimanggu Latosol soil mixed with cow dung (3:1), 10 kg/polybag, arranged in a factorially completely random design with 3 replications. Plot size was 8 polybag/treatment. The first factor was two clones of patchouly : K, = Sidikalang and K2 = Situak. The second factor was 4 levels of water availability: 2J% (A,), 50% (A2). 75% (A,), and 100% (A,) ield capacity (FC). Variables observed were percentage of shoot growth, plant height, leaf area, fresh weight and dry weight, oil content (rendement, colour and patchouly alcohol). The result showed that there was no interaction between the two factors for number of shoots. Clone of Sidikalang had higher plant height than that of Situak. The water availability of 75% (FC) gave optimum growth for the two clones, except the number of leaves. For Situak the water avaibility of 100% (FC) gave the highest number of leaves. For Sidikalang the water availability of 100% gave the highest dry weight of leaves. Oil rendement for Situak with 25% FC was the highest (4.0) with bright yellow colour. The content of patchouly alcohol for Situak was higher than that of Sidikalang (30%). Therefore, it can be concluded that to obtain the optimum growth and the higest production it needed 75 - 100% (FC) water availability, while for high patchouly alcohol content, it needed buzer the water availability, i.e. 25-50% (FC).</p><p>Key words: Patchouli, Pogostemon cablin, water level, growth, production</p>


2012 ◽  
Vol 455-456 ◽  
pp. 1339-1344 ◽  
Author(s):  
Zhe Qi Li ◽  
Jing Yu Liu

Photodegradation ofp-nitrophenol catalyzed by ZnO/MWCNTs composite in water was investigated. The effects of pH, irradiation time, catalyst loading, initial substrate concentration and MWCNTs content on the degradation were investigated. Experiment results revealed that the optimal conditions were ap-nitrophenol concentration of 60.0 mg/L at pH 5.0 with catalyst loading of 10.0 g/L under solar irradiation for the illumination of 180 min. The highest efficiency on photodegradation ofp-nitrophenol can be achieved with an optimal MWCNTs/ZnO mass ratio of 0.16%. Possible decomposing mechanisms were also discussed. The repeatability of photocatalytic activity was tested. The photocatalyst was used ten cycles with degradation efficiency still higher than 95%. The results of the study showed the feasible and potential use of ZnO/MWCNTs composite in degradation of toxic organic pollutants.


2013 ◽  
Vol 315 ◽  
pp. 399-403 ◽  
Author(s):  
Nurulsaidatulsyida Sulong ◽  
Anika Zafiah Mohd Rus

Treatment on the exposed surface to the environmental attack was studied based on biopolymer coating from waste cooking oil doped with a superhydrophilic filler of Titanium Dioxide (TiO2), known as TOP. TOP was found to affect the physical properties of the coated concrete surface in a systematic way. Contact angle measurements are interpreted with respect to nanoand micro-features existing on the surface of the water repellent superhydrophilic filler filled bio-polymer composite coating. The smooth coated surfaces of polymer filled or doped with superhydrophobic filler shows the systematic increasing static Waste Contact Angle, WCA (θst) and revealed that polymer filled superhydrophobic fillers by only 2.0 % shows the ability to form superhydrophobicity property. Scanning Electron Microscope (SEM) pictures revealed the difference between the concrete surface roughness of concrete biopolymer with and without TOP coating is to provide self-cleaning concrete biopolymer coating based on two principal ways: (1) the development of surface coating of semiconducting photocatalytic superhydrophilic. (2) If such a superhydrophilic is illuminated by light, then grease, dirt and organic contaminants will be decomposed and can easily be swept away by rain.


2019 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Yaşar Erayman Yüksel ◽  
Yasemin Korkmaz

Purpose Durability of textile materials under wet conditions has become very important in recent years. The water repellency performance of fabrics should be maintained in the seam areas. The purpose of this paper is to analyze the effect of water repellent agents and sewing threads on the seam and water repellency performance properties of woven fabrics. Design/methodology/approach 100 percent polyester woven fabrics were treated with three different water repellent finishing agents (silicone, fluorocarbons with 6 and 8 carbons) and then sewn with different sewing threads (unfinished/water repellent finished polyester/cotton corespun and polyamide filament). Afterwards, mechanical properties, seam performance and water repellency properties of these materials were measured. Findings The effect of finishing which was statistically significant on seam strength only in warp direction was significant on seam elongation and efficiency in both warp and weft directions. Seam strength, seam efficiency, seam slippage and seam pucker of fabrics sewn with polyamide threads were higher than others. The fluorocarbons applied to the fabrics gave higher water repellency values than silicones. In addition, as the chain length increased in fluorocarbons, water repellency performance increased. Sewing process reduced water resistance of fabrics; however, water repellent finish applied to the threads increased water resistance of fabrics. Originality/value As a result of the literature review, it was seen that water repellency property of a wear were studied in only seamless areas of fabrics. Originality of this study is that the water repellency properties are also analyzed in the seam areas of the fabrics and evaluated together with the seam performance characteristics.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2458 ◽  
Author(s):  
Bruna Raquel Zancopé ◽  
Vanessa B. Dainezi ◽  
Marinês Nobre-dos-Santos ◽  
Sillas Duarte ◽  
Vanessa Pardi ◽  
...  

BackgroundA carbon dioxide (CO2) laser has been used to morphologically and chemically modify the dental enamel surface as well as to make it more resistant to demineralization. Despite a variety of experiments demonstrating the inhibitory effect of a CO2laser in reduce enamel demineralization, little is known about the effect of surface irradiated on bacterial growth. Thus, this in vitro study was preformed to evaluate the biofilm formation on enamel previously irradiated with a CO2laser (λ = 10.6 µM).MethodsFor this in vitro study, 96 specimens of bovine enamel were employed, which were divided into two groups (n = 48): 1) Control-non-irradiated surface and 2) Irradiated enamel surface. Biofilms were grown on the enamel specimens by one, three and five days under intermittent cariogenic condition in the irradiated and non-irradiated surface. In each assessment time, the biofilm were evaluated by dry weigh, counting the number of viable colonies and, in fifth day, were evaluated by polysaccharides analysis, quantitative real time Polymerase Chain Reaction (PCR) as well as by contact angle. In addition, the morphology of biofilms was characterized by fluorescence microscopy and field emission scanning electron microscopy (FESEM). Initially, the assumptions of equal variances and normal distribution of errors were conferred and the results are analyzed statistically by t-test and Mann Whitney test.ResultsThe mean of log CFU/mL obtained for the one-day biofilm evaluation showed that there is statistical difference between the experimental groups. When biofilms were exposed to the CO2laser, CFU/mL and CFU/dry weight in three day was reduced significantly compared with control group. The difference in the genes expression (Glucosyltransferases (gtfB) and Glucan-binding protein (gbpB)) and polysaccharides was not statically significant. Contact angle was increased relative to control when the surface was irradiated with the CO2laser. Similar morphology was also visible with both treatments; however, the irradiated group revealed evidence of melting and fusion in the specimens.ConclusionIn conclusion, CO2laser irradiation modifies the energy surface and disrupts the initial biofilm formation.


2017 ◽  
Vol 7 ◽  
pp. 184798041770279 ◽  
Author(s):  
Baojiang Liu ◽  
Taizhou Tian ◽  
Jinlong Yao ◽  
Changgen Huang ◽  
Wenjun Tang ◽  
...  

A robust superhydrophobic organosilica sol-gel-based coating on a cotton fabric substrate was successfully fabricated via a cost-effective one-step method. The coating was prepared by modification of silica nanoparticles with siloxane having long alkyl chain that allow to reduce surface energy. The coating on cotton fabric exhibited water contact angle of 151.6°. The surface morphology was evaluated by scanning electron microscopy, and surface chemical composition was measured with X-ray photoelectron spectroscopy. Results showed the enhanced superhydrophobicity that was attributed to the synergistic effect of roughness created by the random distribution of silica nanoparticles and the low surface energy imparted of long-chain alkane siloxane. In addition, the coating also showed excellent durability against washing treatments. Even after washed for 30 times, the specimen still had a water contact angle of 130°, indicating an obvious water-repellent property. With this outstanding property, the robust superhydrophobic coating exhibited a prospective application in textiles and plastics.


1969 ◽  
Vol 22 (1) ◽  
pp. 1 ◽  
Author(s):  
IF Wardlaw

Photosynthetic rate, leaf and root extension, dry weight changes, and the translocation of labelled photosynthates were followed in L. temulentum plants subjected to water shortage at a time when the eighth leaf was expanding.


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