Hemp-fiber based nonwoven composites: Effects of alkalization on sound absorption performance

Yılmaz, Nazire Deniz; Powell, Nancy; Banks‐Lee, P.; Michielsen, Stephen

doi:10.1007/s12221-012-0915-0

Cited by 48 publications

(17 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In noise reduction materials, sound absorption material is very common and effective, which is widely used in the noise control engineering. In recent years, the study of porous sound absorption materials has been carried out and abundant achievements have been made (Duan, Cui, Xu, & Liu, 2012;Fouladi, Mohd Nor, Ayub, & Ghassem, 2012;Keshavarz & Ohadi, 2013;Na, Agnhage, & Cho, 2012;Shoshani, 1991;Xiang, Wang, Liu, Zhao, & Xu, 2013;Yilmaz, Powell, Lee, & Michielsen, 2012). Shaoshi (1991) studied sound absorption properties by combinations of multi-layers of non-woven fabric and single layer of woven fabric.…”

Section: Introductionmentioning

confidence: 99%

“…By attaching nano-fibers to common fibers, sound absorption properties strikingly increased. Yilmaz et al (2012) studied the influence of alkalization on sound absorption properties of hemp-fiber composites. As temperature and concentration increased in the process of alkalization, sound absorption properties improved remarkably, while the duration of alkalization had a minor impact.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sound absorption properties of composite structure with activated carbon fiber felts

Shen

Jiang

2014

The Journal of The Textile Institute

View full text Add to dashboard Cite

This paper is intended to study the influence of different factors on the sound absorption properties of composite structure with activated carbon fiber felts. Activated carbon fiber felts made from viscose fiber mats were prepared and later combined with perforated panels to form four different composite sound absorption structures. Based on the transfer function method, the impedance tube was used to test the sound absorption coefficients of composite structure in an acoustic range of 80-6300 Hz frequencies. Analysis was made to discuss the influence of such factors on the sound absorption properties as the position of activated carbon fiber felts, thickness, and air space. The results demonstrated that the composite structure displayed different sound absorption properties at different frequencies.Perforated panels played the dominant role in sound absorption by the occurrence of resonance at 80-3500 Hz frequencies, while porous materials contributed the most at 3500-6300 Hz frequencies. At 80-3500 Hz frequencies, the best performance could be observed in the third type of composite structure with changes in the position of activated carbon fiber; the first resonance frequency of the first type of composite structure and perforated panel structure was basically the same, and that of the remaining three types significantly shifted towards the low frequencies with the same scale. In smaller thickness range, with the increase in the thickness of activated carbon fiber felts, sound absorption coefficients of the first and second types of composite structure increased, the first resonance frequency of the first type showing no apparent shift towards the low frequencies compared with what was shown in the second type; but when the thickness arrived at 15.6 mm, sound absorption properties of the composite structure had similar traits to that performed by porous materials in an acoustic range of 80-6300 Hz frequencies. With the increase in the distance of air space, sound absorption properties were improving at 80-650 Hz frequencies but decreasing at 650-3500 Hz frequencies, the first resonance frequency moving towards the low frequencies. At 3500-6300 Hz frequencies, as the position of activated carbon fiber felts and the distance of air space varied, sound absorption coefficients were basically unchanged; while as thickness increased, sound absorption coefficients improved.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Sound absorption properties of composite structure with activated carbon fiber felts

Shen

Jiang

2014

The Journal of The Textile Institute

View full text Add to dashboard Cite

show abstract

“…The higher reflection and lower sound absorption is due to the dense layer created by the pectin, lignin, hemicellulose, and other lower-molecular weight a b c materials on the surface of the composites. According to Yilmaz et al (2012), the treatment caused the fiber flow resistivity to be reduced, which makes it one of the primary factors influencing reducing the sound absorption coefficients of composites. Figure 6b shows that the surface of untreated luffa fiber composites exhibited unsticking, which is an indication of poor adhesion between luffa fibers and epoxy.…”

Section: Morphological Analysismentioning

confidence: 99%

Processing and Characterization of Epoxy/Luffa Composites: Investigation on Chemical Treatment of Fibers on Mechanical and Acoustical Properties

et al. 2014

View full text Add to dashboard Cite

This study focuses on the development of epoxy/luffa composites and the investigation of their mechanical and acoustical properties. The fibers underwent an alkalization treatment, and its effects on the mechanical and sound absorption properties of the composites were measured utilizing a universal testing machine and two-microphone transfer function impedance tube methods. The effects of chemical modifications on the fibers were studied using a scanning electron microscope (SEM). The thermal analyses of composites were conducted using thermo-gravimetric analysis (TGA). The composite's functional group was identified and evaluated using Fourier transform infrared spectroscopy (FTIR). The sound absorption coefficient of untreated and treated composites across a range of frequencies was very similar. Untreated composites appeared to perform better than those that were treated. Compared with untreated fiber composites, there was an improvement in the tensile strength of the treated fiber composites. The SEM characterization showed that the alkaline treatment changed the morphology of the fibers, resulting in a decrease in the sound absorption coefficients of the composites. The thermal characterization of composites showed that dehydration and degradation of lignin occurred in a temperature range of 40 to 260 °C, and the maximum percentage of cellulose was found to decompose at 380 °C.

show abstract

“…Choe et al tried to improve the sound absorption coefficients of PU foam by adding chemically treated wood fibers and analyzed the influence of open porosity, air‐flow resistance, and tortuosity of the foam materials. Besides, hemp , sisal , flax , and oil palm are also commonly used acoustic material additives.…”

Section: Introductionmentioning

confidence: 99%

Acoustic Characteristics Parameters of Polyurethane/Rice Husk Composites

Wang

Zhang

et al. 2018

Polymer Composites

View full text Add to dashboard Cite

The interest of this article lies in the proposition of develop the relationship of the adding of Rice Husk (RH) and acoustic characteristic parameters of Polyurethane (PU) foam. In this article, different amount of RH (2%, 5%, and 8%) was employed into the formation of PU foam system. A rapid method based on professional acoustic measurement was used to determine the acoustic characteristic parameters of the PU foam and PU‐RH composites, such as porosity, flow resistance, tortuosity, and characteristic constants, and analyze the effect of RH on the acoustic characteristic parameters. The measured results indicated that the sound absorption coefficients of PU‐RH composites increased at low frequency along with a small decrease at high frequency on the addition of RH. And adding more RH will be helpful to improve the low‐frequency sound absorption performance of PU foam without increasing the thickness. With the increase of RH additive amount, the flow resistance decreased first and then increased, while the porosity declined slowly generally. Overall, the PU‐RH composite containing 5% RH showed the most satisfactory absorption performance. POLYM. COMPOS., 40:2653–2661, 2019. © 2018 Society of Plastics Engineers

show abstract

Hemp-fiber based nonwoven composites: Effects of alkalization on sound absorption performance

Cited by 48 publications

References 10 publications

Sound absorption properties of composite structure with activated carbon fiber felts

Sound absorption properties of composite structure with activated carbon fiber felts

Processing and Characterization of Epoxy/Luffa Composites: Investigation on Chemical Treatment of Fibers on Mechanical and Acoustical Properties

Acoustic Characteristics Parameters of Polyurethane/Rice Husk Composites

Contact Info

Product

Resources

About