21 research outputs found
Degree of cross-linking and fiber, yarn, and fabric properties
This article does not have an abstract
Analysis of Flame-retardant Finishes on Textiles Using Laser-Raman Spectroscopy
135-138<span style="font-size:11.0pt;line-height:115%;
font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">Laser-Raman investigations
have been carried out on polyester-cotton blend fabrics finished with various
phosphorus based flame-retarding chemicals. From the spectra obtained, it has
been possible to identify not only the bands characteristic of fibres constituting
the blends but also certain frequencies associated with the vibrations of P-N
and P-CI bonds present in the flame-retardant chemical finish. Though the
application of laser-Raman spectroscopy to the study of the chemical nature of
textile surface chemical finishes is still in its infancy, it seems to provide
more detailed information than is possible through infrared spectroscopy.</span
Studies on Decrystallization of cotton
X-ray methods have been used to measure crystallinity and crystallite dimensions in cotton fibers that have been swollen in aqueous solutions of caustic soda, ethylene diamine, and zinc chloride. Different times, temperatures and concentrations of swelling agent have been used. Optimal decrystallizing conditions are given, together with re sidual crystallinities and crystallite sizes. The inter-relation between crystallinity and crystallite size is discussed
X-ray measurements of crystallinity and crystallite size in swollen and hydrolyzed cottons
Crystallinity and crystallite size determinations have been carried out on a number of samples of swollen, hydrolyzed, and swollen and hydrolyzed cotton fibers, employing X-ray diffraction techniques and a Geiger counter recording spectrometer. A new hi variate analysis technique has been developed in order to determine the crystalline con tent of samples in which two crystalline phases are present, namely cellulose I and II. In the determination of crystallite dimensions the tilted fiber technique has been adopted for measuring crystallite lengths. A new method of resolving superposed line profiles for the measurement of crystallite width has also been developed. The results of these studies seem to suggest that there is a very close relationship between crystallinity and crystallite volume for all the types of chemical treatment studied, and that increasing crystallinity is a measure of increasing crystallite volume. On the other hand, no unique relationship between crystallinity and any one crystallite dimension has emerged for all the treatments studied. However, there are relationships which are specific to different kinds of chemical treatment of cotton
Polyester Fibres Compatible for Blending with Cotton in Blended Fabrics: Part I—Stress-Strain Curves
55-59<span style="font-size:11.0pt;line-height:115%;
font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">An attempt has been made to
alter polyester fibre properties through physical modification using simple
drawing and heat setting operations with a view to producing a compatible fibre
with properly matched stress-strain curves for blending with cotton. It is
observed that the cold-drawn and subsequently tension heat set polyester fibres
give stress-strain curves matching those for some superior cottons and
therefore these fibres can be better alternatives for commercial medium and
high tenacity polyester fibres normally used in India for blending with cotton
for getting apparel fabrics. The new anti-pill polyester fibres can also be
used for blending with cotton provided they are heat set under tension. When
these fibres are stretched beyond their original length and heat set under
tension, their stress-strain curves match those for most cotton fibres.</span
The chemical composition of the diatom frustule
This paper describes the X-ray diffraction studies carried out on a large number of present-day, as well as fossil diatom frustules. From the diffraction patterns given by the various specimens, it has been concluded that the silica present in diatom frustules is not in an amorphous or sub-colloidal state as was spposed by previous workers but that it is crystalline α -quartz. Although crystalline α -quartz is present in present-day diatoms, the degree of crystallisation is much less than in the fossilized specimens. In addition to the crystalline quartz content, there is present in all diatoms an organic component which might possibly be a protein. In the present-day diatoms this organic component occurs in considerable proportion so that its X-ray diffraction pattern tends to mask the pattern due to crystalline α-quartz. On fossilization, however, a considerable amount of the protein content is lost, while the silica content becomes more predominant, and more and more crystalline with time. Evidence for the occurrence of pectin in diatoms is also presented
Peripheral Acid Hydrolysis of Crosslinked Viscous Medium
91-99<span style="font-size:11.0pt;line-height:115%;
font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">Crosslinks formed between
cellulose chains to impart durable press properties to the treated cotton
fabrics differ considerably in their resistance to acids. Fabrics crosslinked
by the pad-dry-cure technique were treated with sulphuric acid of different
concentrations in a viscous medium to obtain peripheral hydrolysis of
crosslinks, washed and air dried. Greater dye uptake by the acid treated
samples than pad-dry-cure controls at comparable nitrogen contents indicates
that the resin is peripherally hydrolyzed for these fabrics. These fabrics
exhibit higher abrasion resistance, higher wet crease recovery and lower tensile
strength then the pad-dry-cure samples at comparable dry crease recovery levels.
Electron microscopical observations also lend support to the conclusion that
hydrolysis of crosslinks at the surface of pad-dry-cure fabrics has been
achieved by treating with sulphuric acid in a highly viscous medium.</span