Influence of Multilayer Textile Biopolymer Foam Doped with Titanium Dioxide for Sound Absorption Materials

2013 ◽  
Vol 594-595 ◽  
pp. 750-754 ◽  
Author(s):  
Anika Zafiah M. Rus ◽  
Nik M. H. Normunira ◽  
Rahimah Abd Rahim
Keyword(s):  
Titanium Dioxide ◽  
Sound Absorption ◽  
Fiber Diameter ◽  
Low Frequency ◽  
Polyester Fabric ◽  
Fiber Density ◽  
Fiber Properties ◽  
Acoustic Study ◽  
Number Of Layers ◽  
Frequency Level

Biopolymer foam was prepared by the reaction of bio-monomer based on vegetable oil with commercial Polymethane Polyphenyl Isocyanate (Modified Polymeric-MDI) and titanium dioxide (TiO2). The acoustic study of biopolymer foam with 2.5% TiO2 loading was examined by impedance tube test according to the ASTM E-1050 and laminated with three types of textile such as polyester, cotton and single knitted jersey. It was revealed that the thicker the fabric the higher the sound absorption coefficient (α) at low frequency level. The higher the number of layers or thickness of the fabric, the sound absorption through the fabric increases at low frequency but after the maximum it remains almost unaltered. Three layer of cotton fabric gives maximum α approximately equal to 0.578 which is 1.472mm thickness at low frequency level of 1000-2000Hz and single knitted jersey gives maximum α at 3th layer. Meanwhile , the α of biopolymer foam with 2.5% TiO2 loading laminated with polyester fabric approximately equal to 1 at lower frequency level of 1000-2000Hz with lower thickness that is 0.668mm. Polyester fabric with lowest thickness shows better α at lower frequency level due to the structure of the fabric. The relationships among the fiber properties such as fiber density, fiber diameter, fibrous material layer were considered as a factor that influences the sound absorption property.

Influences of Thickness and Fabric for Sound Absorption of Biopolymer Composite

2013 ◽  
Vol 393 ◽  
pp. 102-107 ◽  
Author(s):  
Nik Normunira Mat Hassan ◽  
Anika Zafiah Mohd Rus
Keyword(s):  
Sound Absorption ◽  
Fiber Diameter ◽  
Polyester Fabric ◽  
Medium Frequency ◽  
Fiber Density ◽  
Fiber Properties ◽  
Tube Test ◽  
Acoustic Study ◽  
Number Of Layers ◽  
Frequency Level

Biopolymer foam was prepared by the reaction of bio-monomer based on vegetable oil with commercial Polymethane Polyphenyl Isocyanate (Modified Polymeric-MDI). The acoustic study of biopolymer foam was examined by impedance tube test according to the ASTM E-1050 and laminated with three types of textile such as polyester, cotton and single knitted jersey. It was revealed that the thicker the fabric the higher the sound absorption coefficient (α) at medium frequency level. The higher the number of layers or thickness of the fabric, the sound absorption through the fabric increases at medium frequency but after the maximum it remains almost unaltered. Three layer of cotton fabric gives maximum α approximately equal to 1 which is 1.104 mm thickness at frequency level of 3000-3500Hz and single knitted jersey gives maximum α at 4thlayer of 2200-2700Hz. Meanwhile , the α of biopolymer foam laminated with polyester fabric approximately equal to 1 at lower frequency level of 2000-3000Hz with lower thickness that is 0.668mm. Polyester fabric with lowest thickness shows better α at lower frequency level due to the structure of the fabric. The relationships among the fiber properties such as fiber density, fiber diameter, and fibrous material layer were considered as a factor that influences the sound absorption property.

Influence of High Doping of TiO2 of Polymeric Foam for Acoustic Study

2013 ◽  
Vol 594-595 ◽  
pp. 755-759
Author(s):  
Anika Zafiah M. Rus ◽  
M.A. Bainun Akmal ◽  
N.N. Mat Hassan
Keyword(s):  
Titanium Dioxide ◽  
High Frequency ◽  
Sound Absorption ◽  
Absorption Property ◽  
Polymer Foam ◽  
Polymeric Foam ◽  
Acoustic Study ◽  
Frequency Level ◽  
Reduction Coefficient ◽  
Coefficient Method

Titanium dioxide represents an effective photocatalyst for water and air purification and for self-cleaning surfaces. The purpose of this study is to determine sound absorption property of polymer foam of high doping of Titanium Dioxide (TiO2) which are 20%, 40%, 60%, 80% and 100%. The acoustic study of the samples was measured by using impedance tube test according to the ASTM E-1050 to determined sound absorption coefficient (α) and noise reduction coefficient method (NRC). The highest α is 0.999 observed from the polymer foam doped with 60% of TiO2 at high frequency level of 4000 Hz. Meanwhile, the highest doping of TiO2 polymer foam shows remarkable characteristic of low level frequency absorption at 2000 Hz. Thus, different percentage of TiO2 doped in polymer foam can be used successfully to alter the characteristic of sound absorption property in a systematic way according to the request application.

Sound absorption and thermal insulation properties of composite thermoplastic polyurethane/polystyrene (TPU/PS) nanofiber web and TPU nanofiber web and PS-extracted TPU/PS microfiber web

2021 ◽  
pp. 152808372110395
Author(s):  
Neslihan Karaca ◽  
İlkay Özsev Yüksek ◽  
Nuray Uçar ◽  
Ayşen Önen ◽  
Cafer Kirbaş
Keyword(s):  
Thermal Conductivity ◽  
Thermal Insulation ◽  
Sound Absorption ◽  
Composite Nanofibers ◽  
Fiber Diameter ◽  
Thermoplastic Polyurethane ◽  
Low Frequency ◽  
Soxhlet Extraction ◽  
Nanofiber Web ◽  
Potential Use

In this study, composite thermoplastic polyurethane (TPU)/polystyrene (PS) nanofiber web and TPU nanofiber web and PS-extracted TPU/PS microfiber web have been experimentally investigated with regard to sound absorption and thermal conductivity coefficients to observe a potential use in sound and thermal insulation areas. Moreover, other properties such as surface area, morphology, tensile strength/elongation, air permeability, and thermal degradation have been analyzed. It has been observed that nanofiber web properties such as fiber diameter, extensibility, pore volume, and porosity have been clearly changed by Soxhlet extraction of PS from the composite TPU/PS nanofibers. PS-extracted TPU/PS fibers can be preferred for the low frequency (600–800 Hz) due to higher SAC (0.7). On the other hand, TPU nanofibers were more effective at medium frequencies (around 3000 Hz, SAC 0.6). Both TPU and PS-extracted TPU/PS composite fibers had similar thermal conductivities, whereas TPU/PS composite nanofibers had lowest thermal conductivity (0.05 W/mK) with moderate maximum SAC value (around 1000 Hz, SAC 0.5–0.6).

Acoustic Study Based on Sustainable Green Polymer Treated with H2O

2013 ◽  
Vol 748 ◽  
pp. 281-285 ◽  
Author(s):  
Nik Normunira Mat Hassan ◽  
Anika Zafiah M. Rus ◽  
S. Nurulsaidatulsyida ◽  
Siti Rahmah Mohid
Keyword(s):  
Cell Size ◽  
Morphological Study ◽  
Average Pore Size ◽  
Acoustic Property ◽  
Low Frequency ◽  
Polymer Foam ◽  
Average Pore ◽  
Acoustic Study ◽  
Frequency Level ◽  
Green Polymer

Green polymer foam was prepared by the reaction of green monomer based on vegetable oil with commercial Polymethane Polyphenyl Isocyanate (Modified Polymeric-MDI) and distilled water (H2O). The morphological study of green polymer foam was examined by Scanning Electron Microscope (SEM) and acoustic property by means of H2O composition ratio equivalent to weight of polyol. It was found that the cell size of green polymer foam has significantly increment as well as H2O loading increased. Increasing of H2O more than 50% equivalent to weight of polyol shows nonuniform pore distribution, large average pore size and smallest number of pore. Furthermore, the cell size of neat green polymer foam gives 400μm up to 1833.3μm with high loading of H2O. In addition, the cell size of green polymer foam influences by the increasing amount of H2O loading and enhanced the sound absorption property at low frequency level.

scholarly journals Effect of Porous Materials Combination in Layers on Sound Absorption Characteristics

2015 ◽  
Vol 773-774 ◽  
pp. 210-215
Author(s):  
Muhd Hafeez Zainulabidin ◽  
M.H.M. Yusuff ◽  
Al Emran Ismail ◽  
M.Z. Kasron ◽  
A.S.M. Kassim
Keyword(s):  
Absorption Coefficient ◽  
Sound Absorption ◽  
Low Frequency ◽  
Sound Absorption Coefficient ◽  
Frequency Range ◽  
Sound Absorber ◽  
Number Of Layers ◽  
Combination Number ◽  
Impedance Tubes ◽  
Absorption Characteristics

This paper describes the investigation and analysis on two materials in which one material is a relatively good sound absorber at low frequency range and another is a relatively good sound absorber at high frequency range, combined together in layers to form a better sound absorber for a wider range of frequencies. The layer combinations of the materials are varied and the values of Sound Absorption Coefficient, α are measured experimentally by using impedance tubes with two microphones transfer function method according to ISO 10534-2 standard. The results obtained are compared in terms of the order of material and the number of layer combinations of materials for each sample. The orders of combinations and number of layers of combinations have significant influence on the sound absorption characteristics. The order of materials has reversed effect on Sound Absorption Coefficient, α as the number of layer combination is increased. Increase in the combination number will make the specimen performed relatively better at a wider frequency range.

Quantitative Diameter Measurements of Chromatin and TMV Fibers in the Freeze-Dried State

1988 ◽  
Vol 46 ◽  
pp. 170-171
Author(s):  
B. D. Athey ◽  
A. L. Stout ◽  
M. F. Smith ◽  
J. P. Langmore
Keyword(s):  
Reliable Method ◽  
Fiber Diameter ◽  
Quantitative Agreement ◽  
One Dimension ◽  
Fiber Axis ◽  
Two Dimensional ◽  
Fiber Density ◽  
Variable Diameter ◽  
Freeze Dried ◽  
Expected Values

Although there is general agreement that Inactive chromosome fibers consist of helically packed nucleosomes, the pattern of packing is still undetermined. Only one of the proposed models, the crossed-linker model, predicts a variable diameter dependent on the length of DNA between nucleosomes. Measurements of the fiber diameter of negatively-stained and frozen- hydrated- chromatin from Thyone sperm (87bp linker) and Necturus erythrocytes (48bp linker) have been previously reported from this laboratory. We now introduce a more reliable method of measuring the diameters of electron images of fibrous objects. The procedure uses a modified version of the computer program TOTAL, which takes a two-dimensional projection of the fiber density (represented by the micrograph itself) and projects it down the fiber axis onto one dimension. We illustrate this method using high contrast, in-focus STEM images of TMV and chromatin from Thyone and Necturus. The measured diameters are in quantitative agreement with the expected values for the crossed-linker model for chromatin structure

Highly Efficient Low‐Frequency Broadband Sound Absorption with a Composite Hybrid Metasurface

2021 ◽  
Author(s):  
Qingxuan Liang ◽  
Yutao Wu ◽  
Peiyao Lv ◽  
Jin He ◽  
Fuyin Ma ◽  
...  
Keyword(s):  
Sound Absorption ◽  
Low Frequency ◽  
Highly Efficient ◽  
Broadband Sound
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