Rearch on the Water Repellency of Inorganic Insulation Mortar

2013 ◽  
Vol 687 ◽  
pp. 262-265
Author(s):  
Wen Guan ◽  
Bei Hong Ye ◽  
Li Qun Zhao ◽  
Jin Qi Xuan

Three kinds of methods to improve the hydrophobicity of inorganic insulation mortar is studied in this paper.The results show that, the three methods have different influences on the water absorption rate of inorganic insulation mortar. Adding silane in mortar effects most and the surface modification of vitrified small ball effects least. Using the surface modification of vitrified small ball and spraying silane on the mortar surface together has little influence on the water repellency of mortar. However using of adding silane in mortar and spraying silane on the mortar surface together has remarkable influence. Using the three methods together will effect most.

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
H. C. Cheng ◽  
M. S. Chen ◽  
B. Y. Peng ◽  
W. T. Lin ◽  
Y. K. Shen ◽  
...  

The conventional orthodontic power chain, often composed of polymer materials, has drawbacks such as a reduction of elasticity owing to water absorption as well as surface discoloration and staining resulting from food or beverages consumed by the patient. The goal of this study was to develop a surface treatment (nanoimprinting) for orthodontic power chains and to alleviate their shortcomings. A concave template (anodic alumina) was manufactured by anodization process using pure aluminum substrate by employing the nanoimprinting process. Convex nanopillars were fabricated on the surface of orthodontic power chains, resulting in surface treatment. Distinct parameters of the nanoimprinting process (e.g., imprinting temperature, imprinting pressure, imprinting time, and demolding temperature) were used to fabricate nanopillars on the surface of orthodontic power chains. The results of this study showed that the contact angle of the power chains became larger after surface treatment. In addition, the power chains changed from hydrophilic to hydrophobic. The power chain before surface treatment without water absorption had a water absorption rate of approximately 4%, whereas a modified chain had a water absorption rate of approximately 2%–4%. Furthermore, the color adhesion of the orthodontic power chains after surface modification was less than that before surface modification.


2014 ◽  
Vol 911 ◽  
pp. 40-44 ◽  
Author(s):  
Muhammad Aqif Adam ◽  
Alawi Sulaiman ◽  
Che Mohd Som Said ◽  
Ayub M. Som ◽  
Azhari Samsu Bahruddin ◽  
...  

Palm oil industry produces huge amount of oil palm decanter cake (OPDC). Currently it is not yet commercialized however due to its characteristics, it can be used to produce oil palm decanter cake natural polymer composite (OPDC-NPC). NPC is a type of material made by combining natural fiber with polymer. Therefore the objective of this paper is to produce NPC from OPDC and then determine its mechanical and physical properties such as elasticity, stiffness, tensile strength and water absorption rate. The OPDC samples were collected from Felda Trolak Palm Oil Mill. Prior to NPC development, the oil was removed from OPDC using hexane soxhlet extraction method. OPDC-NPC was fabricated using molding method where the mixture of 95% polypropylene (PP) and 5% OPDC were mixed using twin-screw extruder. The results showed that OPDC-NPC has an elasticity of 2231 MPa, stiffness of 30 MPa, tensile strength of 32 MPa and water absorption rate of 0.16 % which was slightly better with the other types of fibers.


2021 ◽  
Vol 2129 (1) ◽  
pp. 012059
Author(s):  
Sitti Fatimah Mhd Ramle ◽  
Aqilah Abdul Rahim ◽  
Nur Hafizzah Jusoh ◽  
Nurul Fazita Mohammad Rawi ◽  
Che Ku Abdullah Che Ku Alam

Abstract In recent times, awareness on plastic pollution had increase which brings innovation on new productions to be environmental friendly. Various polymers has been used to analyse the suitability to produce thin films. In this study, Poly lactic acid (PLA) and Polybutylene adipate terephthalate (PBAT) reinforced with microcrystalline cellulose (MCC) were investigated. MCC were produced from selected bamboo for obtaining cellulose, then followed by an acidic hydrolysis process for the processing of microcrystalline cellulose (MCC). In this study, the thin film are focusing on the barrier properties such as water absorption, solvent resistance and absorption test. From the results shows that, the lowest rate of water absorption rate is 1.9% by 1% B-MCC/PLA/PBAT, meanwhile, the highest rate of water absorption is 60.1% by 5% C-MCC/PLA/PBAT. The water absorption rate decrease gradually with the decreasing of amount of MCC in the samples. Lastly, the thin film samples can resist with oleic acid solvents as the condition of thin film samples is still remain but they were not resistance with xylene as the thin film samples were shrinked and degraded. This thin film have a potential to replace the non-biodegradable petrochemical polymer based on their properties such as food contact, availability and cost.


2018 ◽  
Vol 30 (3) ◽  
Author(s):  
Chai Teck Jung ◽  
Tang Hing Kwong ◽  
Koh Heng Boon

Abstract: This paper presents some experimental results and discusses the used of recycled foamed aggregates as natural coarse aggregates replacement in producing concrete. The physical properties of recycled foamed aggregates concrete were investigated. The properties studied are water absorption and drying shrinkage from the concrete early ages until the periods of 56 days. The 100 mm x 100 mm cube specimen was used to study the water absorption at the age of 7, 28 and 56 days. Meanwhile, the 100 mm x 100 mm x 300 mm length prism had been casted and used for drying shrinkage test for recycled foamed aggregates concrete. The foamed aggregates was produced from crushing recycled foamed concrete blocks. It were coated with cement paste to reduce its water absorption ability during casting process. Superplasticizer was used to maintain the workability of fresh concrete with a slump vary between 50 mm to 100 mm. The physical tests were conducted on recycled foamed aggregates to determine their initial properties such as loose bulk density, sieve analysis and water absorption rate. Recycled foamed aggregate concretes were produced with varied water cement ratio. The results obtained indicated that the linear elastic relationship between water cement ratio and water absorption rate. The higher the water cement ratio of concrete specimen will obtained higher water absorption rate. Vice versa, the density is low for drying shrinkage. The water absorption decreased while drying shrinkage becomes more stabilized over curing period.


2019 ◽  
Vol 2019 ◽  
pp. 1-19 ◽  
Author(s):  
Zhiming Ma ◽  
Qin Tang ◽  
Dingyi Yang ◽  
Guangzhong Ba

Since China hosted the Olympic Games in 2008, a mass of construction and demolition (C&D) wastes were produced with the rapid urbanization construction. Recycling the C&D waste into recycled aggregates (RA) is an effective method for reducing the amount of C&D wastes. Many studies on the properties of RA and the durability of recycled aggregate concrete (RAC) were conducted in China over the past decade. Due to the restrictions of various languages, some valuable studies on the durability of RAC are hard to be acquired by the scholars around the world. Therefore, this paper is developed to review the studies on the durability of RAC in China, and the shrinkage behavior, chloride permeability, carbonation behavior, and freeze-thaw resistance of RAC are, respectively, introduced. Considering the waste concrete, bricks, and ceramics used in preparing RA are frequently mixed together in China, this study proposes an index of average water absorption rate to quantify the effects of RA types, quality, and replacement percentages on the durability of RAC. Meanwhile, the relationship between the average water absorption rate of RA and the durability parameters of RAC is established. Finally, the improving methods of RAC durability are introduced, and the RA particle shaping and carbonation modification are emphasized.


2012 ◽  
Vol 550-553 ◽  
pp. 62-70 ◽  
Author(s):  
Ning Bo Leng ◽  
Shun Xi Wang ◽  
Pei Han

Selecting ammonium dihydrogen phosphate of ultra-fine processing and surface modification as the main agent of fire extinguishing agent, mica powder, activated clay, talc, calcium carbonate as an inert filler, ND1 as additive, developed specifically for the grassland fire characteristics of ultra-fine dry powder fire extinguishing agent grassland; tested the moisture absorption rate, water repellency, bulk density and fluidity and other technical indicators; using quadrat grassed ignition method on new grassland fire extinguishing agent research the fire extinguishing efficiency and cost.


2014 ◽  
Vol 665 ◽  
pp. 192-195 ◽  
Author(s):  
Yu Zheng ◽  
Chang Sheng Pan ◽  
Jian Li ◽  
He Chi Pan ◽  
Jun Yi Hu ◽  
...  

Foam concrete products had high absorption rate due to a large number of bubbles dispersion in it.which has serious effects upon the overall thermal performance of material and the durability of construction.Three methods were studied which includes Organic Silicon hydrophobic agent、High fatty acids hydrophobic agent and hydrophobic agent F in order to reduce the water absorption rate.Results show that the water absorption rate was reduced significantly with mixed High fatty acids. The water absorption rate drops of 68.2%, and the organic silicon is in a second place , and the hydrophobic agent F is the worst.


2020 ◽  
Vol 24 (1) ◽  
pp. 55-59
Author(s):  
Guopeng Wu ◽  
Wenwu Chen ◽  
Kai Cui

In order to study the influence of dry-wet cycling on the deterioration characteristics of gypsum rocks and solve the problems encountered in engineering construction, in this study, gypsum rocks are taken as the research object. With the combination of laboratory test and theoretical analysis, the numerical simulation of particle flow is carried out, and the deterioration characteristics of physical and mechanical properties of gypsum rock under dry-wet cycling are studied. The results show that gypsum, quartz, zeolite and dolomite are the main components of gypsum rocks. Gypsum occupies the most components in gypsum rocks, so the various characteristics of gypsum greatly affect the characteristics of gypsum rocks. The process of water absorption and loss of gypsum is similar, which shows that the rate of water absorption or loss of gypsum is faster in the early stage, and tends to be stable in the later stage. The curve of the whole process of water absorption and loss is fitted by negative exponential function, and the effect is better. The larger the porosity of gypsum rock is, the better its water absorption performance is. Intergranular pore, dissolution pore and dissolution pore are the main pore types of gypsum rock. Intergranular pore is the main water absorption channel of gypsum rock. The cumulative water absorption increases with the increase of wetting and drying cycles. The change of water absorption curve is mainly manifested in water absorption rate and time. The more the number of wet-dry cycles is, the higher the water absorption rate in the early stage of water absorption is, the closer the characteristic curve to the coordinate axis of water absorption is, and the shorter the water absorption time is. In contrast, the shape difference of water loss curve is very small. It can be seen from this that in the process of wetting and drying cycle, the hydrophysical and hydrochemical processes promote each other, which changes the crystal structure and pore structure of gypsum rocks, reduces the crystal strength and increases the porosity, thus leading to the deterioration of the mechanical properties of gypsum rocks.


1998 ◽  
Vol 6 (A) ◽  
pp. A325-A328
Author(s):  
T.L. Hong ◽  
Samson C.S. Tsou ◽  
S.-J. Tsai

Soya bean, as the raw material for tofu processing, is required to be of high quality. The variety characteristics, storage conditions and harvesting seasons of soya bean are the major contributors to soya bean quality. This study attempted to use near infrared (NIR) spectroscopy to evaluate the processing quality of soya bean. Evaluation models using NIR spectroscopy were developed for the analyses of tannin content, degrees of lipid oxidation, detection of harvest seasons and measurement of water absorption rate. Simulation experiments demonstrated that these models were not only able to analyse major compositions of soya bean, but also to sort out soya bean samples and their suitability for tofu making regardless of various defects, such as high tannin content, low water absorption rate, prolonged storage and unfavourable harvest seasons. Statistic analysis suggested that these models could be used as mass-screening techniques for breeding programmes and quality control measures in tofu-processing factories.


1996 ◽  
Vol 43 (3) ◽  
pp. 288-298 ◽  
Author(s):  
Jinfa RIE ◽  
Makoto MIURA ◽  
Shin-ichi TANEYA

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