Fibre Analysis

Question 1

What are the 4 factors that affect the transfer of fibres?

Answer 1

size of the contact area
contact pressure
how long contact for
nature of donor and recipient fabrics

Question 2

What are the 4 factors that affect the rate of loss of fibres?

Answer 2

the activity level of recipient garment
contact of the recipient with other surfaces
the strength of the initial transfer
nature of recipient fabric

Question 3

Name 2 natural fibres and examples of them.

Answer 3

vegatable fibres = cellulose, lignin

Animal fibres = proteins

Question 4

Name 2 manufactured fibres and examples of them.

Answer 4

Synthetic fibres = polymers

regenerated fibres = treated cellulose

Question 5

What is a hazard with mineral fibres?

Answer 5

if you breathe them in they can cause a tumour

Question 6

What is the most prevalent plant fibre?

Answer 6

cotton

Question 7

What are seed fibres (natural fibre)?

Answer 7

hairs attached to seeds of plants (cotton)

Question 8

What are bast fibres (natural fibre)?

Answer 8

form in bundles in stalk/stem (flax, hemp)

Question 9

What are leaf fibres (natural fibre)?

Answer 9

leaves + leaf stalks (sisal, abaca)

Question 10

What are fruit fibres (natural fibre)?

Answer 10

from husks/fruit (coir)

Question 11

What is wool made from?

Answer 11

keratin

Question 12

What is silk made from?

Answer 12

fibroin

Question 13

How are man-made fibres made?

Answer 13

force polymeric material through holes of spinner

Question 14

What were the first two man-made fibres?

Answer 14

Rayon
Nylon
1911

Question 15

What are regenerated fibres (man-made fibre)?

Answer 15

made from regenerated cellulose

nylon, acetate, triacetate

Question 16

What are synthetic fibres (man-made fibre)?

Answer 16

synthetic chemicals called polymers

nylons, polyesters, acrylics

Question 17

Stereomicroscope

Answer 17

produced 3D image
offer large working distance
can be lighted from below or vertically from above
should be used first to examine fibres

Question 18

Name 8 features noted when looking at fibres under a microscope?

Answer 18

crimp
length
colour
relative diameter
lustre
apparent cross-section
damage
adhering debris

Question 19

What are the 7 methods of collection of fibres?

Answer 19

tweezers
tape lift
1:1 lift
scraping
vacuuming
combing
cuttings/pullings

Question 20

Name 7 ways of analysing fibres?

Answer 20

polarised light microscopy
fluorescence electron microscopy
microspectrophotometry
FTIR
FTIR-ATR
GCMS
fibre dye analysis

Question 21

Polarised light microscopy

Answer 21

easy, quick and non-destructive way to determine the polymer class of synthetic fibres
isotropic material
-the molecule has no specific or regular orientation of agreement
anisotropic
- molecules have a regular and specific orientation
-drawing process in synthetic fibres production makes them anisotropic
-will display certain optical characteristics which can be exploited to identify their genetic class.
studies interaction of plane polarised light with the anisotropic substances
refractive indices, the birefringence of synthetic fibres can be determined

Question 22

Fluorescence microscopy

Answer 22

there are substances in fibre that fluoresce when illuminated with a certain range of excitation energy

• optical brightness
• dyes
• pigments
• contaminants

Question 23

Microspectrophotometry

Answer 23

can be applied to a single fibre
non-destructive
can discriminate between fibres of the same colour
allows analysis of light absorption by the fibre in the visible and UV region of the electromagnetic spectrum
absorbance of fibre plotted against wavelength

Question 24

Scanning Electron Microscope

Answer 24

can magnify x100,000
coupled with EDM used as imaging and microanalytical tool in characterisation of fibres
surface morphology can be examined with great depth of field

Question 25

FTIR

Answer 25

highly discriminating
faster sampling
no sample preparation
uses diamond cells

Question 26

Pyrolysis

Answer 26

destructive
molecule fragments in an inert atmosphere and under high temp
used to identify the generic class of unknown fibre

Question 27

Fibre dye analysis

Answer 27

dye extracted from fibre and analysed by TLC

highly inexpensive but destructive