The potential of Raman spectroscopy in distinguishing between wool and mohair fibres
- Authors: Notayi, Mzwamadoda
- Date: 2020
- Subjects: Textile fabrics , Textile fibers -- Mechanical properties Wool -- Dissertations Mohair -- Dissertations
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/49248 , vital:41614
- Description: The possible application of the FT Raman, Raman micro-spectroscopy and ATR-FTIR micro-spectroscopy, have been investigated for distinguishing between wool and mohair. Highly identical Raman and FTIR spectra were obtained from the two fibre types, indicating that indeed they share similar basic molecular structural chemistry. The analysis of the amide I through curve fitting of wool and mohair FT Raman spectra showed that the protein and polypeptide secondary structure exists mainly in the α-helical structural conformation with smaller proportions of β-pleated sheet and β-Turns. These proportions, however, could not be used to distinguish between wool and mohair, due to the significant overlap observed between the two fibres. This study also determined the disulphide contents for possibly distinguishing between wool and mohair fibres, with the average and standard deviation values of 0.20±0.04 and 0.17±0.03 for wool and mohair, respectively, being found. Despite the mean values being found to differ statistically significant (p<0.05), a considerable overlap was observed, posing a doubt in the possible application of the method for distinguishing between the two fibres and blend composition analysis of the two fibres. The application of ratiometric analysis, based on the relative peak heights of certain FT Raman bands, showed that a combination of ratios A (I2932/I1450) and D (I508/I1450) could hold great potential in distinguishing between wool and mohair fibre samples. The individual values of ratios A and D varied a great deal from one mohair sample to the other and even more from one wool sample to another, with the individual values for ratio A ranging from 2.71-3.68 and 2.35-3.08 for wool and mohair, respectively, while ratio D ranged from 0.18-0.32 and 0.17-0.22 for wool and mohair, respectively. An important observation from this study is that if, for an unknown sample, if individual values of ratios A and D exceed 3.1 and 0.22, respectively, are found then the sample is most likely to be either a pure wool or blend of wool and mohair, whereas if all the values fall below the two threshold values, then the unknown sample can be declared a pure mohair sample. A Raman spectral database or library of approximately 100 high quality Raman average spectra of wool and mohair fibres has been established for the Bruker 80V FTIR/Raman spectrophotometer at the Nelson Mandela University (NMU). Although this has not been fully validated due to the unforeseen frequent breakdown encountered with the FT Raman system, at this stage, it has been realized that verification of unknown materials is highly possible. A great need for the development of a classification model based on multivariate or chemometrics has been realized. An ATR-FTIR LUMOS micro-spectroscopic system was also investigated for the possible application in distinguishing between wool and mohair single fibres. The amide I/II band ratios were determined for both wool and mohair fibres to distinguish between the two fibre types. The mean and standard deviation values of 1.20±0.02 and 1.21±0.01 for mohair and wool, respectively, were found and were shown not to differ statistically significant (p˃0.05). The secondary structure analysis showed that the content of the α-helical secondary structure might be different between the two fibre types, with a great overlap of individual values, however, being observed between the two fibre types (wool and mohair), raising concerns in the possible application of the α-helical content for distinguishing the two fibres.
- Full Text:
- Date Issued: 2020
- Authors: Notayi, Mzwamadoda
- Date: 2020
- Subjects: Textile fabrics , Textile fibers -- Mechanical properties Wool -- Dissertations Mohair -- Dissertations
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/49248 , vital:41614
- Description: The possible application of the FT Raman, Raman micro-spectroscopy and ATR-FTIR micro-spectroscopy, have been investigated for distinguishing between wool and mohair. Highly identical Raman and FTIR spectra were obtained from the two fibre types, indicating that indeed they share similar basic molecular structural chemistry. The analysis of the amide I through curve fitting of wool and mohair FT Raman spectra showed that the protein and polypeptide secondary structure exists mainly in the α-helical structural conformation with smaller proportions of β-pleated sheet and β-Turns. These proportions, however, could not be used to distinguish between wool and mohair, due to the significant overlap observed between the two fibres. This study also determined the disulphide contents for possibly distinguishing between wool and mohair fibres, with the average and standard deviation values of 0.20±0.04 and 0.17±0.03 for wool and mohair, respectively, being found. Despite the mean values being found to differ statistically significant (p<0.05), a considerable overlap was observed, posing a doubt in the possible application of the method for distinguishing between the two fibres and blend composition analysis of the two fibres. The application of ratiometric analysis, based on the relative peak heights of certain FT Raman bands, showed that a combination of ratios A (I2932/I1450) and D (I508/I1450) could hold great potential in distinguishing between wool and mohair fibre samples. The individual values of ratios A and D varied a great deal from one mohair sample to the other and even more from one wool sample to another, with the individual values for ratio A ranging from 2.71-3.68 and 2.35-3.08 for wool and mohair, respectively, while ratio D ranged from 0.18-0.32 and 0.17-0.22 for wool and mohair, respectively. An important observation from this study is that if, for an unknown sample, if individual values of ratios A and D exceed 3.1 and 0.22, respectively, are found then the sample is most likely to be either a pure wool or blend of wool and mohair, whereas if all the values fall below the two threshold values, then the unknown sample can be declared a pure mohair sample. A Raman spectral database or library of approximately 100 high quality Raman average spectra of wool and mohair fibres has been established for the Bruker 80V FTIR/Raman spectrophotometer at the Nelson Mandela University (NMU). Although this has not been fully validated due to the unforeseen frequent breakdown encountered with the FT Raman system, at this stage, it has been realized that verification of unknown materials is highly possible. A great need for the development of a classification model based on multivariate or chemometrics has been realized. An ATR-FTIR LUMOS micro-spectroscopic system was also investigated for the possible application in distinguishing between wool and mohair single fibres. The amide I/II band ratios were determined for both wool and mohair fibres to distinguish between the two fibre types. The mean and standard deviation values of 1.20±0.02 and 1.21±0.01 for mohair and wool, respectively, were found and were shown not to differ statistically significant (p˃0.05). The secondary structure analysis showed that the content of the α-helical secondary structure might be different between the two fibre types, with a great overlap of individual values, however, being observed between the two fibre types (wool and mohair), raising concerns in the possible application of the α-helical content for distinguishing the two fibres.
- Full Text:
- Date Issued: 2020
Job creation and income generation in the cultural and creative industries: a case study of the shweshwe sewing industry
- Authors: Mapuma, Aviwe Simbonge
- Date: 2019
- Subjects: Textile industry -- South Africa -- Eastern Cape , Clothing trade -- South Africa -- Eastern Cape , Sewing -- South Africa -- Eastern Cape , Job creation -- South Africa -- Eastern Cape , Textile manufacturers -- South Africa -- Eastern Cape , Textile fabrics , Income -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/122948 , vital:35378
- Description: Worldwide, there has been a growing realisation of the importance of Cultural and Creative Industries as a driving force for employment creation, income generation and economic growth. Therefore, there is a need in South Africa to study and understand these industries setting, and business environment. Shweshwe is a unique local fabric produced by Da Gama Textiles in the Eastern Cape province of South Africa. This fabric is used by many micro-enterprises as an input to make clothes and other items for traditional cultural celebrations and ceremonies. This study is about the micro-enterprises who use South Africa made textiles (i.e. shweshwe textile) as business input. More specifically, it looks at employment creation and income generation opportunities of the micro-enterprises that use shweshwe textile as an input. These micro-enterprises and shweshwe production are being threatened by the rising influx of cheaper ready-made imported clothes that mimic the shweshwe designs and colours, in some cases, the logo as well. This study also plans to estimate the size and discover the attributes of the micro-enterprises that use shweshwe as an input in their businesses in South Africa, in order to estimate the impact of the counterfeit shweshwe imports on those micro-enterprises. This study adopted a mixed-methods approach-using a combination of both qualitative and quantitative data collection methods. Face-to-face interviews with questionnaires, were done with a total sample of 62 owners of the micro-enterprises that use shweshwe as input, in the Western Cape (Cape Town) and Eastern Cape (i.e. Makhanda and East London), South Africa. Self-administered questionnaires were emailed to 20 Jackson’s Stores managers across the country. Lastly, face-to-face interviews were done with the key stakeholder-the representative of Cowie trading (the main shweshwe distributor) and Da Gama Textiles (the factory of shweshwe), during a field visit. The Qualitative data was analysed using thematic analysis, whereas the quantitative data was analysed using inferential and descriptive statistics. The results show, that the micro-enterprises that use shweshwe as input are a significant contributor in terms of employment creation and income generation in South Africa. They also reveal that there is a big number of micro-enterprises that use shweshwe as an input in SA. The findings showed an estimate of between 5077 and 6000 small businesses that are using shweshwe an input, which are associated with 10 900 to 12 900 jobs. It was also found out that there is a transformation in this industry, and that this sector is B-BEE compliant. There are also high levels of human capital in this industry. This is an important finding revealing that there is potential for future growth in this sector. Results also found that the majority micro-enterprise owners (80%) have no other source of income, meaning that they are highly reliant on their shweshwe sewing business income. Additionally, 85% of those business, shweshwe garments makes up half or more of their sewing business proceeds. This reveals that a decline in income caused by the import of ready-made clothes in “fake” shweshwe will have a negative impact on the micro-enterprises’ ability to contribute to economic growth and job creation in this industry. To show the impact of the import of ready-made clothes in “fake” shweshwe on the micro-enterprises’ ability to contribute to economic growth and job creation in this industry. In the questionnaires that were used to conduct face-to-face interviews with the micro-enterprises, respondents were asked to indicate whether they had other sources of income other than the income they generate from the shweshwe sewing business. They were further asked as follow up question to choose from a given list of possible options containing a range of percentages of their business income that comes from the work sewn with shweshwe. This question was asked in order to be able to see, if there were to be a decline in income caused by the import of ready-made clothes in “fake” shweshwe what impact it would have on the micro-enterprises that use shweshwe as an input. The theory of industrial organisation has adopted the view of that businesses operating in the formal sector are more efficient and productive than those in the informal sector (Lobato, 2010). The study found that the micro-enterprises that operate in the formal sector generate more turnover than the ones that operate in the informal sector. However, the theory was further tested by running OLS regression, the results showed that operating in the informal sector does not affect turnover when other variables are controlled for, however, that it does affect job creation. In closing, this thesis provides suggestions on how to support, and protect the micro-enterprises that use shweshwe as an input, in order to enhance this industry’s potential also to ensure its continuous contribution in terms of employment creation and income generation in South Africa.
- Full Text:
- Date Issued: 2019
- Authors: Mapuma, Aviwe Simbonge
- Date: 2019
- Subjects: Textile industry -- South Africa -- Eastern Cape , Clothing trade -- South Africa -- Eastern Cape , Sewing -- South Africa -- Eastern Cape , Job creation -- South Africa -- Eastern Cape , Textile manufacturers -- South Africa -- Eastern Cape , Textile fabrics , Income -- South Africa -- Eastern Cape
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/122948 , vital:35378
- Description: Worldwide, there has been a growing realisation of the importance of Cultural and Creative Industries as a driving force for employment creation, income generation and economic growth. Therefore, there is a need in South Africa to study and understand these industries setting, and business environment. Shweshwe is a unique local fabric produced by Da Gama Textiles in the Eastern Cape province of South Africa. This fabric is used by many micro-enterprises as an input to make clothes and other items for traditional cultural celebrations and ceremonies. This study is about the micro-enterprises who use South Africa made textiles (i.e. shweshwe textile) as business input. More specifically, it looks at employment creation and income generation opportunities of the micro-enterprises that use shweshwe textile as an input. These micro-enterprises and shweshwe production are being threatened by the rising influx of cheaper ready-made imported clothes that mimic the shweshwe designs and colours, in some cases, the logo as well. This study also plans to estimate the size and discover the attributes of the micro-enterprises that use shweshwe as an input in their businesses in South Africa, in order to estimate the impact of the counterfeit shweshwe imports on those micro-enterprises. This study adopted a mixed-methods approach-using a combination of both qualitative and quantitative data collection methods. Face-to-face interviews with questionnaires, were done with a total sample of 62 owners of the micro-enterprises that use shweshwe as input, in the Western Cape (Cape Town) and Eastern Cape (i.e. Makhanda and East London), South Africa. Self-administered questionnaires were emailed to 20 Jackson’s Stores managers across the country. Lastly, face-to-face interviews were done with the key stakeholder-the representative of Cowie trading (the main shweshwe distributor) and Da Gama Textiles (the factory of shweshwe), during a field visit. The Qualitative data was analysed using thematic analysis, whereas the quantitative data was analysed using inferential and descriptive statistics. The results show, that the micro-enterprises that use shweshwe as input are a significant contributor in terms of employment creation and income generation in South Africa. They also reveal that there is a big number of micro-enterprises that use shweshwe as an input in SA. The findings showed an estimate of between 5077 and 6000 small businesses that are using shweshwe an input, which are associated with 10 900 to 12 900 jobs. It was also found out that there is a transformation in this industry, and that this sector is B-BEE compliant. There are also high levels of human capital in this industry. This is an important finding revealing that there is potential for future growth in this sector. Results also found that the majority micro-enterprise owners (80%) have no other source of income, meaning that they are highly reliant on their shweshwe sewing business income. Additionally, 85% of those business, shweshwe garments makes up half or more of their sewing business proceeds. This reveals that a decline in income caused by the import of ready-made clothes in “fake” shweshwe will have a negative impact on the micro-enterprises’ ability to contribute to economic growth and job creation in this industry. To show the impact of the import of ready-made clothes in “fake” shweshwe on the micro-enterprises’ ability to contribute to economic growth and job creation in this industry. In the questionnaires that were used to conduct face-to-face interviews with the micro-enterprises, respondents were asked to indicate whether they had other sources of income other than the income they generate from the shweshwe sewing business. They were further asked as follow up question to choose from a given list of possible options containing a range of percentages of their business income that comes from the work sewn with shweshwe. This question was asked in order to be able to see, if there were to be a decline in income caused by the import of ready-made clothes in “fake” shweshwe what impact it would have on the micro-enterprises that use shweshwe as an input. The theory of industrial organisation has adopted the view of that businesses operating in the formal sector are more efficient and productive than those in the informal sector (Lobato, 2010). The study found that the micro-enterprises that operate in the formal sector generate more turnover than the ones that operate in the informal sector. However, the theory was further tested by running OLS regression, the results showed that operating in the informal sector does not affect turnover when other variables are controlled for, however, that it does affect job creation. In closing, this thesis provides suggestions on how to support, and protect the micro-enterprises that use shweshwe as an input, in order to enhance this industry’s potential also to ensure its continuous contribution in terms of employment creation and income generation in South Africa.
- Full Text:
- Date Issued: 2019
Studies on acoustic properties of non-woven fabrics
- Authors: Mvubu, Mlando Basel
- Date: 2017
- Subjects: Needlepunch (Nonwoven fabric) Nonwoven fabrics , Textile fabrics
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/19387 , vital:28866
- Description: This study is divided in to two main parts. The first part deals with the optimization of process parameters of needle-punched non-woven fabrics for achieving maximum sound absorption by employing a Box-Behnken factorial design. The influence of fibre type, depth of needle penetration and stroke frequency on sound absorption properties were studied. These parameters were varied at three levels during experimental trials. From multiple regression analysis, it was observed that the depth of needle penetration alone was the most dominant factor among the selected parameters, which was followed by the interaction between depth of needle penetration and stroke frequency. Fibre type was the least dominant parameter affecting sound absorption. A maximum sound absorption coefficient of 47% (0.47) was obtained from the selected parameters. The results showed that for a process such as needle-punching, which is influenced by multiple variables, it is important to also study the interactive effects of process parameters for achieving optimum sound absorption. The second part of the study deals with the effect of type of natural fibre (fineness), and the blending ratio (with PET fibres) on the air permeability of the needle-punched non-woven fabrics and then it proceeds to study the effect of the air-gap, type of natural fibre (fineness) and blending ratio (with PET fibres) on sound absorption of needle-punched non-woven fabrics. These parameters are tested individually and their two way interaction (synergy) effect using ANOVA. The air-gap was varied from 0mm to 25mm with 5mm increments, three natural fibre types were used and all were blended with polyester fibres at three blending ratios for each natural fibre type. The Univariate Tests of Significance shows that all three parameters have a significant effect on sound absorption together with two two-way interactions, with the exception of the Blend Ratio × Air Gap two-way interaction which was not significant. It was found that the sound absorption improves with the increase in the air-gap size up to 15mm after which sound absorption decreased slightly with the further increase in the air-gap up to 25mm.
- Full Text:
- Date Issued: 2017
- Authors: Mvubu, Mlando Basel
- Date: 2017
- Subjects: Needlepunch (Nonwoven fabric) Nonwoven fabrics , Textile fabrics
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/19387 , vital:28866
- Description: This study is divided in to two main parts. The first part deals with the optimization of process parameters of needle-punched non-woven fabrics for achieving maximum sound absorption by employing a Box-Behnken factorial design. The influence of fibre type, depth of needle penetration and stroke frequency on sound absorption properties were studied. These parameters were varied at three levels during experimental trials. From multiple regression analysis, it was observed that the depth of needle penetration alone was the most dominant factor among the selected parameters, which was followed by the interaction between depth of needle penetration and stroke frequency. Fibre type was the least dominant parameter affecting sound absorption. A maximum sound absorption coefficient of 47% (0.47) was obtained from the selected parameters. The results showed that for a process such as needle-punching, which is influenced by multiple variables, it is important to also study the interactive effects of process parameters for achieving optimum sound absorption. The second part of the study deals with the effect of type of natural fibre (fineness), and the blending ratio (with PET fibres) on the air permeability of the needle-punched non-woven fabrics and then it proceeds to study the effect of the air-gap, type of natural fibre (fineness) and blending ratio (with PET fibres) on sound absorption of needle-punched non-woven fabrics. These parameters are tested individually and their two way interaction (synergy) effect using ANOVA. The air-gap was varied from 0mm to 25mm with 5mm increments, three natural fibre types were used and all were blended with polyester fibres at three blending ratios for each natural fibre type. The Univariate Tests of Significance shows that all three parameters have a significant effect on sound absorption together with two two-way interactions, with the exception of the Blend Ratio × Air Gap two-way interaction which was not significant. It was found that the sound absorption improves with the increase in the air-gap size up to 15mm after which sound absorption decreased slightly with the further increase in the air-gap up to 25mm.
- Full Text:
- Date Issued: 2017
Characterization of animal fibres
- Authors: Notayi, Mzwamadoda
- Date: 2014
- Subjects: Animal fibres , Textile fabrics , Animal science
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10552 , http://hdl.handle.net/10948/d1020426
- Description: Identification of fibres, particularly in blends, requires knowledge of their characteristics. Individual Identifying features between wool and mohair fibres were investigated in this study using a Scanning Electron Microscope (SEM), Fourier Transform Infrared-Attenuated Total Reflection (FTIR-ATR), Fourier Transform Raman and Atomic Force Microscope (AFM). This study confirmed that wool and mohair can be differentiated and identified in blends using the cuticle scale height (CSH) criterion, wool having an average CSH of 0.6 ± 0.1 μm and mohair having an average CSH of 0.4 ± 0.1 μm. The AFM provided highly reproducible CSH results, which also confirmed the SEM results that indeed wool and mohair could be differentiated using the CSH as criterion. The AFM gave a CSH value of 0.9 ± 0.2 μm for wool and 0.6 ± 0.2 μm for mohair, the difference between the two results being statistically significant according to the student t-test. It has been demonstrated that wool and mohair identification in blends is possible, by using the AFM to measure CSH, although the method is very time consuming and might be expensive. The FTIR-ATR showed similar spectra for wool and mohair fibres, confirming that the two fibre types consist of the same polymer material. Nevertheless, a difference was observed in the ratios of the relative intensities of the amide I (around 1630 cm-1) to the amide II (around 1515cm-1) absorption bands. The FT Raman provided similar spectra for the wool and mohair fibres, although a possible distinguishing feature between the two fibres could be the intensities of the alkyl side chains chemical band near 2940 cm-1 in the spectra of the two fibre types. According to the results obtained in this study, the FTIR-ATR and the FT Raman techniques may have potential for differentiating between wool and mohair but this requires further investigation.
- Full Text:
- Date Issued: 2014
- Authors: Notayi, Mzwamadoda
- Date: 2014
- Subjects: Animal fibres , Textile fabrics , Animal science
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10552 , http://hdl.handle.net/10948/d1020426
- Description: Identification of fibres, particularly in blends, requires knowledge of their characteristics. Individual Identifying features between wool and mohair fibres were investigated in this study using a Scanning Electron Microscope (SEM), Fourier Transform Infrared-Attenuated Total Reflection (FTIR-ATR), Fourier Transform Raman and Atomic Force Microscope (AFM). This study confirmed that wool and mohair can be differentiated and identified in blends using the cuticle scale height (CSH) criterion, wool having an average CSH of 0.6 ± 0.1 μm and mohair having an average CSH of 0.4 ± 0.1 μm. The AFM provided highly reproducible CSH results, which also confirmed the SEM results that indeed wool and mohair could be differentiated using the CSH as criterion. The AFM gave a CSH value of 0.9 ± 0.2 μm for wool and 0.6 ± 0.2 μm for mohair, the difference between the two results being statistically significant according to the student t-test. It has been demonstrated that wool and mohair identification in blends is possible, by using the AFM to measure CSH, although the method is very time consuming and might be expensive. The FTIR-ATR showed similar spectra for wool and mohair fibres, confirming that the two fibre types consist of the same polymer material. Nevertheless, a difference was observed in the ratios of the relative intensities of the amide I (around 1630 cm-1) to the amide II (around 1515cm-1) absorption bands. The FT Raman provided similar spectra for the wool and mohair fibres, although a possible distinguishing feature between the two fibres could be the intensities of the alkyl side chains chemical band near 2940 cm-1 in the spectra of the two fibre types. According to the results obtained in this study, the FTIR-ATR and the FT Raman techniques may have potential for differentiating between wool and mohair but this requires further investigation.
- Full Text:
- Date Issued: 2014
A comparative study of the comfort related properties of commercial apparel fabrics containing natural and man-made fibres
- Authors: Stoffberg, Marguerite Ester
- Date: 2013
- Subjects: Textile fabrics , Materials -- Thermal properties
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10455 , http://hdl.handle.net/10948/d1020931
- Description: The relationship between the fabric parameters, as independent variables, and the comfort related properties, as dependent variables, of commercial suiting fabrics, containing both natural and man-made fibres, have been studied. The fabric parameters measured in the study were mass, thickness, density, and air permeability. The comfort related properties, tested on a Permetest instrument, included water vapour permeability, water vapour resistance, and thermal resistance, with the moisture permeability index being derived. A total of 26 commercial suiting fabrics, covering a wide range of mass, as well as different fibre types and blends and fabric structures, was tested. The fibres covered, included wool, polyester, viscose, and cotton, while the fabric structures covered were 1x1 plain weave, 2x1 twill and 2x2 twill weave. The objectives of this study were to determine the empirical relationships between the measured fabric properties and the measured comfort related properties, and to determine the role, if any, of fibre type and fabric structure, since many claims are made in practice concerning the relative advantages, in terms of comfort, of a specific fibre type or blend, or fabric structure, over others, some of which being supported by research results. Since the fabrics covered, were commercial and were not engineered so that the different fabric parameters (independent variables) and fibre type and blend, as well as fabric structure could be varied independently of each other, the effects of the various fabric parameters on the fabric comfort related properties were determined and quantified by multiple regression analyses (multi-linear and multi-quadratic), and the best fit regression equations, and contribution of each parameter to the overall fit established. It was found that fabric thickness and fabric mass had the largest effect on the comfort related properties as measured here, fabric mass determining, to a large extent, water vapour permeability, and fabric thickness, thermal resistance. The rest of the fabric parameters included in the study had only a relatively small effect on the measured comfort related properties. The influence of fabric parameters, with particular reference to mass and thickness, on the measured comfort related properties, were much greater than that of fibre type or blend, or fabric structure. It was, therefore, concluded from this study, that the fabric parameters, as opposed to the intrinsic characteristics of a particular fibre, whether natural or man-made, largely determined those fabric comfort related properties measured here.
- Full Text:
- Date Issued: 2013
- Authors: Stoffberg, Marguerite Ester
- Date: 2013
- Subjects: Textile fabrics , Materials -- Thermal properties
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10455 , http://hdl.handle.net/10948/d1020931
- Description: The relationship between the fabric parameters, as independent variables, and the comfort related properties, as dependent variables, of commercial suiting fabrics, containing both natural and man-made fibres, have been studied. The fabric parameters measured in the study were mass, thickness, density, and air permeability. The comfort related properties, tested on a Permetest instrument, included water vapour permeability, water vapour resistance, and thermal resistance, with the moisture permeability index being derived. A total of 26 commercial suiting fabrics, covering a wide range of mass, as well as different fibre types and blends and fabric structures, was tested. The fibres covered, included wool, polyester, viscose, and cotton, while the fabric structures covered were 1x1 plain weave, 2x1 twill and 2x2 twill weave. The objectives of this study were to determine the empirical relationships between the measured fabric properties and the measured comfort related properties, and to determine the role, if any, of fibre type and fabric structure, since many claims are made in practice concerning the relative advantages, in terms of comfort, of a specific fibre type or blend, or fabric structure, over others, some of which being supported by research results. Since the fabrics covered, were commercial and were not engineered so that the different fabric parameters (independent variables) and fibre type and blend, as well as fabric structure could be varied independently of each other, the effects of the various fabric parameters on the fabric comfort related properties were determined and quantified by multiple regression analyses (multi-linear and multi-quadratic), and the best fit regression equations, and contribution of each parameter to the overall fit established. It was found that fabric thickness and fabric mass had the largest effect on the comfort related properties as measured here, fabric mass determining, to a large extent, water vapour permeability, and fabric thickness, thermal resistance. The rest of the fabric parameters included in the study had only a relatively small effect on the measured comfort related properties. The influence of fabric parameters, with particular reference to mass and thickness, on the measured comfort related properties, were much greater than that of fibre type or blend, or fabric structure. It was, therefore, concluded from this study, that the fabric parameters, as opposed to the intrinsic characteristics of a particular fibre, whether natural or man-made, largely determined those fabric comfort related properties measured here.
- Full Text:
- Date Issued: 2013
Investigating the possibility of using wild silk fancy yarns to produce upholstery fabrics for home furniture
- Authors: Somi, Bongiwe Promrose
- Date: 2013
- Subjects: Textile design , Textile fabrics
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/7616 , vital:22103
- Description: About a decade ago an attempt to build a viable wild silk industry, prompted by the discovery of the naturally available wild silk cocoons in the North West Province of South Africa, was made and a degumming plant was established in the Ganyesa village. The challenges faced in that establishment soon brought the developments to a standstill and cited among the problems was the lack of designer input in the production stages, which resulted in poor quality products. Focusing on the design problem the intention of this research is to explore a more effective design and production method for the wild silk fabrics. Through assessing the previously produced fabrics in order to identify their limitations, and by experimenting with innovative fabric production processes, a suitable aesthetic quality can be added to the final products. Starting with the investigation of current trends and choosing a design theme as a guide for the production process, fabric samples intended for use in upholstery of home furniture are developed. With the objective of successfully achieving a balance between aesthetic appeal and suitability for the intended end use, the fabrics are subjected to performance assessments based on internationally recognised standards. From the findings of this research it is therefore envisaged that, from the design aspect, proper redevelopment of the South African wild silk industry could encourage further involvement from textile designers. This would bring more improvement to the fabrics produced and encourage their use in different applications.
- Full Text:
- Date Issued: 2013
- Authors: Somi, Bongiwe Promrose
- Date: 2013
- Subjects: Textile design , Textile fabrics
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/7616 , vital:22103
- Description: About a decade ago an attempt to build a viable wild silk industry, prompted by the discovery of the naturally available wild silk cocoons in the North West Province of South Africa, was made and a degumming plant was established in the Ganyesa village. The challenges faced in that establishment soon brought the developments to a standstill and cited among the problems was the lack of designer input in the production stages, which resulted in poor quality products. Focusing on the design problem the intention of this research is to explore a more effective design and production method for the wild silk fabrics. Through assessing the previously produced fabrics in order to identify their limitations, and by experimenting with innovative fabric production processes, a suitable aesthetic quality can be added to the final products. Starting with the investigation of current trends and choosing a design theme as a guide for the production process, fabric samples intended for use in upholstery of home furniture are developed. With the objective of successfully achieving a balance between aesthetic appeal and suitability for the intended end use, the fabrics are subjected to performance assessments based on internationally recognised standards. From the findings of this research it is therefore envisaged that, from the design aspect, proper redevelopment of the South African wild silk industry could encourage further involvement from textile designers. This would bring more improvement to the fabrics produced and encourage their use in different applications.
- Full Text:
- Date Issued: 2013
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