Research on Fibrillated Nanofibers and Application of High Efficiency Filter Material

2011 ◽  
Vol 335-336 ◽  
pp. 411-414 ◽  
Author(s):  
Yu Tian ◽  
Yun Liang ◽  
Yan Cui ◽  
Zeng Zhang
Keyword(s):  
Pore Size Distribution ◽  
Glass Fiber ◽  
Pore Size ◽  
High Efficiency ◽  
Negative Impact ◽  
Filter Material ◽  
Air Permeability ◽  
Burst Strength ◽  
Opposite Trend ◽  
Lyocell Fiber

Abstract. The nanofiber based filtering material, made up of fibers of diameter less than 1000 nm, have been discovered as new filtering material for effective filtrations. Lyocell fiber is a kind of regenerated fiber which can be easily fibrillated and brought no negative impact on the recovery of filter material.The present study focuses on how the Lyocell fiber changes with the intensity of beating and compares the effect of nano-fibrillated Lyocell fiber（61°SR） and micro glass fiber（44°SR） on the properties of filter material. The results show that the length, diameter, distortion and degree of fibrillation of Lyocell fiber changes obviously by beating, and a mass of nano-fibril appeared after intensive beating. At the same time, the air permeability and pore size distribution is similar when the content of fibrillated Lyocell fiber and micro glass fiber are the same in filter material; What’s more, the strength of filter material increases with the percentage of fibrillated Lyocell fiber increasing, But the micro glass gets an opposite trend. The burst strength of the filter material with 20 wt.% fibrillated Lyocell fiber is 336KPa, with 20 wt.% micro glass fiber is 71KPa.This study has shed some light on the application of Lyocell fiber to improve the accuracy of filter material effectively.

Preparation and Characterization of Fibrillated Nanofibrous Filter Material

2014 ◽  
Vol 936 ◽  
pp. 327-331 ◽  
Author(s):  
Tian Yu ◽  
Yan Bin Jiang ◽  
Jian Hu
Keyword(s):  
High Efficiency ◽  
Fiber Material ◽  
Filter Material ◽  
Air Permeability ◽  
Filtration Efficiency ◽  
Structure And Properties ◽  
Nanofiber Morphology ◽  
Opposite Trend ◽  
The Impact

The nanofiber, which diameter less than 1000 nm, has been discovered as advanced fiber material for high efficiency filtration. Tencel fiber is a new kind of regenerated fiber which can be easily fibrillated by a mechanical beating process to form nanofiber morphology. The present study shows the nanofiber morphology of Tencel fiber and investigates how the structure and properties of filter material change with the impact of fibrillated nanofiber. The results show a mass of nanofibril appeared after the Tencel fiber is intensively beat. At the same time, the air permeability and pore size of filter material is decreased with the decrease of fibrillated nanofiber content while the strength gets an opposite trend. Whats more, the filtration efficiency of the filter material is significantly enhanced by fibrillated nanofiber which filtration rate achieves 6.3 for particles bigger than 4 μm at 20 wt%. This paper has shed some light on the application of fibrillated fibrillated nanofiber to enhance the efficiency of filter material effectively.

scholarly journals Development of Needle-Punched Nonwoven Fabrics from Reclaimed Fibers for Air Filtration Applications

2014 ◽  
Vol 9 (1) ◽  
pp. 155892501400900 ◽  
Author(s):  
S. Sakthivel ◽  
Anban J.J. Ezhil ◽  
T. Ramachandran
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Air Permeability ◽  
Filtration Efficiency ◽  
Raw Material ◽  
Fine Tuning ◽  
Physical Parameters ◽  
Air Filtration ◽  
Nonwoven Fabrics

This paper reports an investigative study on the fabrication and measurement of the air permeability, mechanical properties, pore size distribution, and filtration efficiency of different nonwoven fabrics produced from reclaimed fibers by analytically changing the machine variables to manipulate the physical parameters of the nonwoven fabrics. Reclaimed fiber of cotton (60%) and polyester (40%) blend was used, so that the prospect of value addition to an inexpensive source of raw material could be explored. The changes in air permeability were interpreted in terms of fabric density profile and pore size distribution. The filtration parameters of filtration efficiency, dust holding capacity, and pressure drop were also calculated. Additionally, the effects of calendering on pore size and filtration properties were evaluated to discover the opportunity of fine-tuning and the performance of the filters. The outcome in this study reflected an overall development in all filtration characteristics due to the calendering operation.

scholarly journals Estimation of air permeability function from soil-water characteristic curve

2019 ◽  
Vol 56 (4) ◽  
pp. 505-513
Author(s):  
Qian Zhai ◽  
Harianto Rahardjo ◽  
Alfrendo Satyanaga
Keyword(s):  
Distribution Function ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Soil Water ◽  
Unsaturated Soil ◽  
Characteristic Curve ◽  
Air Permeability ◽  
Size Distribution Function ◽  
Soil Water Characteristic Curve ◽  
Permeability Function

The multiphase flow (including liquid flow and air flow) in unsaturated soil is related to many engineering problems such as contaminant transport, rainwater infiltration, and soil-water evaporation. It is proven that water flow in unsaturated soil can be estimated using the concept of the pore-size distribution function. Many models have been proposed to estimate the water flow or water permeability function, kw, from the soil-water characteristic curve (SWCC). On the other hand, a limited model has been proposed to estimate the air flow or air permeability function, ka, from the SWCC. Most of the models used for the estimation of the air permeability functions are empirical, and they are dependent on the empirical parameters. In this paper, the relative air coefficient of permeability was estimated using the concept of the pore-size distribution function. In the method proposed in this paper, no empirical parameters were adopted, and the estimation results purely depended on the soil-water characteristic curve. The proposed method was verified against experimental data from published literature.

scholarly journals Prediction of Relative Air Permeability of Porous Media With Weibull Pore Size Distribution

2019 ◽  
Vol 55 (11) ◽  
pp. 10037-10049
Author(s):  
Zhenlei Yang ◽  
Binayak P. Mohanty ◽  
Yalchin Efendiev ◽  
Zhuping Sheng
Keyword(s):  
Porous Media ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Air Permeability

scholarly journals The Pore Size Distribution of Naturally Porous Cigarette Paper and its Relation to Permeability and Diffusion Capacity

2015 ◽  
Vol 26 (7) ◽  
Author(s):  
Bernhard Eitzinger ◽  
Maria Gleinser ◽  
Stefan Bachmann
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Filler Content ◽  
Air Permeability ◽  
Size Distributions ◽  
Diffusion Capacity ◽  
Pore Size Distributions ◽  
Cigarette Paper ◽  
And Diffusion

SummaryThe pore size distribution of cigarette paper determines its air permeability and diffusion capacity and thereby has a significant influence on the gas exchange of a cigarette through the cigarette paper during smoking and during smouldering. For the design of cigarettes and in particular of cigarette papers it is important to understand how the pore size distribution of the cigarette paper is affected by the paper composition and paper properties and how it influences air permeability and diffusion capacity.It was the aim of this study to investigate how the composition of the cigarette paper such as filler content, fibre type and burn additive content qualitatively influenced the pore size distribution and how the pore size distribution and, in particular, which pore size range is correlated with air permeability and diffusion capacity, respectively. To this end eight naturally porous cigarette papers were selected which differed in air permeability, diffusion capacity, fibre type, filler content and burn additive content. The pore size distributions of these papers were measured by mercury porosimetry before and after the papers had been heated to 230 °C for 30 min. The pore size distributions were investigated for qualitative differences when air permeability, fibre type and filler content of the cigarette paper are modified. Furthermore by appropriate weighting of the pore size distributions optimal correlations between a weighted pore volume and air permeability or diffusion capacity were determined. The results show a good correlation with correlation coefficients greater than 0.9 for air permeability as well as for diffusion capacity. The results indicate that large pores are better correlated with changes in air permeability, while small pores are more strongly correlated with changes in diffusion capacity and support previous theoretical results obtained from flow and diffusion models. They also demonstrate the tight relationship between pore size distribution, air permeability and diffusion capacity, which makes the pore size distribution a tool to further optimize cigarette papers, for example, with respect to carbon monoxide yields in the smoke of a cigarette. [Beitr. Tabakforsch. Int 26 (2015) 312-319]

Surface modification of self-assembled isoporous polymer membranes for pressure-dependent high-resolution separation

2019 ◽  
Vol 10 (23) ◽  
pp. 3201-3209 ◽  
Author(s):  
Yang Ou ◽  
Di Zhou ◽  
Zhi-Kang Xu ◽  
Ling-Shu Wan
Keyword(s):  
Surface Modification ◽  
High Resolution ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
High Efficiency ◽  
Polymer Membranes ◽  
Narrow Pore Size Distribution ◽  
Great Performance ◽  
Self Assembled

Polymer membranes with narrow pore size distribution demonstrate great performance in high-resolution and high-efficiency separation.

The influence of high temperature treatment on morphology and performance of superfine glass fiber felts

2020 ◽  
Vol 90 (19-20) ◽  
pp. 2292-2303
Author(s):  
Feiyan Wang ◽  
Jianyong Yu ◽  
Xunmei Liang ◽  
Shide Lu ◽  
Chunfeng Zhao ◽  
...  
Keyword(s):  
Fractal Dimension ◽  
Glass Fiber ◽  
Pore Size ◽  
Fractal Dimensions ◽  
Air Permeability ◽  
Temperature Treatment ◽  
Heat Treatments ◽  
High Temperature Treatment ◽  
And Performance ◽  
The Relationship

This article presents an investigation on effects of heat treatments in the range 400–700℃ on morphology, fractal dimension, pore size distribution, and air permeability of superfine glass fiber felts. During the heat treatments, the released residual stress, thermal decomposition, and thermal contraction make fibers bend to different degrees, corresponding with different fractal dimensions. The felt pores are formed by the random interlacing of fibers, varying with the different bending degree of fibers, which results in an influence on the air permeability of the felt. The results show that there was no visible change in the morphology of the heated felt at 400–550℃. However, the treatment at 600℃ could cause the breakage of some fibers, and above 650℃ the damage of felts. The fractal dimension of heated felt decreased at 400 and 450℃, but then increased above 500℃. The lowest fractal dimension was 1.8827 at 450℃, and the highest was 1.9666 at 600℃. Besides, the pores tend to distribute in a smaller size and a narrower scale under high temperatures, resulting in a decrease in the air permeability. However, the air permeability had the same variation trend with fractal dimension at 400 and 450℃, but opposite above 500℃. The relationship among them was verified by comparing the experimental and theoretical results. At 600℃, the mean pore size and the air permeability reduced by 16% and 31%, respectively.

Study on Pore Structure of Multi-Layered Spunbonded Nonwovens

2013 ◽  
Vol 750-752 ◽  
pp. 103-106
Author(s):  
Chen Yan Zhu ◽  
Wei Wei Ying ◽  
Xiao Fang Zhan ◽  
Xin Lei
Keyword(s):  
Pore Structure ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Air Permeability ◽  
Layer Number ◽  
Structure Morphology ◽  
Maximum Pore Size ◽  
Morphology Characteristics

In this study, three kinds of single-layered spunbonded nonwovens with different specifications were prepared as materials. The relation between layer number and pore structure (morphology characteristics, pore size and pore distribution, and Solid Volume Fraction) was studied. The results show that mean pore size decreases as layer number increases and the degree tends to be gentle. But the change law of maximum pore size is not obvious. Furthermore, pore size distribution of single-layered or two-layered nonwovens is concentrated and further increase in layer number doesnt have obvious effects on it . Air permeability reduces when the layer number increases and the variation trend accords with that of mean pore size.

The microstructure of functionalized poLyacrylonitrile beads for bioseparations

1990 ◽  
Vol 48 (4) ◽  
pp. 1094-1095
Author(s):  
Eduardo A. Kamenetzky ◽  
David A. Ley
Keyword(s):  
Aqueous Solution ◽  
Affinity Chromatography ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Surface Coverage ◽  
Vacuum Impregnation ◽  
Thin Sections ◽  
Selective Staining ◽  
Low Viscosity ◽  
Diamond Knife

The microstructure of polyacrylonitrile (PAN) beads for affinity chromatography bioseparations was studied by TEM of stained ultramicrotomed thin-sections. Microstructural aspects such as overall pore size distribution, the distribution of pores within the beads, and surface coverage of functionalized beads affect performance properties. Stereological methods are used to quantify the internal structure of these chromatographic supports. Details of the process for making the PAN beads are given elsewhere. TEM specimens were obtained by vacuum impregnation with a low-viscosity epoxy and sectioning with a diamond knife. The beads can be observed unstained. However, different surface functionalities can be made evident by selective staining. Amide surface coverage was studied by staining in vapor of a 0.5.% RuO4 aqueous solution for 1 h. RuO4 does not stain PAN but stains, amongst many others, polymers containing an amide moiety.

Sign in / Sign up

Export Citation Format

Share Document