How ordered the fibre is
Many fibres, such as nylon and polyester, are semi-crystalline: ordered, rigid regions sit between disordered, mobile ones. Spinning, drawing and heat setting change the proportion and the arrangement. These changes decide the strength, the elongation, the shrinkage and the dyeing behaviour of the fibre.
Where it is used
- Nylon, polyester and polypropylene fibres and yarns
- Fibres made with different spinning speeds, draw ratios or heat-setting conditions
- Experimental fibres in development
Typical tasks are comparing fibres from different process settings, following how drawing or heat setting changes the rigid share, and relating that to the properties of the fibre.
Rigid parts fade fast, mobile parts last
As with other semi-crystalline polymers, the signal right after the pulse separates a rigid part, which fades almost at once, from a mobile part, which lasts longer. The ratio of the two is a measure of the order in the fibre, and samples are compared on the same scale.
What it adds
- Non-destructive, with little preparation
- A quick comparison of many samples from process trials
- A direct view of mobility, which complements X-ray diffraction, calorimetry and density measurements
- No solvents
Points that matter in practice
- Mostly a research and development tool. Absolute values need a calibration against a technique that you trust, and the ranking of samples is the first use
- The mobile part depends on how the fibre has been conditioned, so treat all samples in the same way before measuring
- Orientation and the packing of the sample in the tube can affect the result, so prepare the samples consistently
- It does not replace tests of strength, shrinkage or dyeing, which are the properties that matter in the end
From your fibres to a method
Send or bring representative samples. MSY Consulting runs feasibility measurements, helps you plan the comparison and the reference technique, and supports the analysis.
Let's talk about your application
Send an email describing your instrument and your application, and you will get a reply.
contact@msyconsulting.euMSY CONSULTING SAS · Wissembourg, France · LinkedIn