GB2390434A

GB2390434A - A sample holding device, or pocket, allowing the containment and subsequent analysis of materials within a dynamic mechanical analyser (DMA)

Info

Publication number: GB2390434A
Application number: GB0215234A
Authority: GB
Inventors: John Charles Duncan; John Stanley Fisher; Keith Edward Ernest Pettitt; Jeffrey Glynn Van-De-Velde
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-07-02
Filing date: 2002-07-02
Publication date: 2004-01-07
Also published as: GB0215234D0

Abstract

A Pocket, usually of an inert material, provides a suitable vessel for holding unusual materials such as a powder, in the analytical head of a stiffness measuring device, such as a dynamic mechanical analyser (Figure 4). The pocket comprises, in one embodiment, a steel shim which has been folded over and the sample placed in the thus formed trough. A temperature sensor may be placed in the trough prior to closure by sealing or welding.

Description

1 2390434

A SAMPLE HOLDING DEVICE, OR POCKET, ALLOWING THE

CONTAINMENT AND SUBSEQUENT ANALYSIS OF MATERIALS

WI'l'HlN A DYNAMIC MECHANICAL ANALYSER (DMA) The invention relates to a device allowing powders, liquids, solid films, foams, bars or any other sample form of material to be mounted within a Dynamic Mechanical l'hcnnal Analyscr (alternatively described as a DMA, Dynamic Mechanical Spectrometer(OMS) or any other device or instrument that measures the stiffness of a malarial).

DMAs arc well known instruments used for characterizing materials such as polymers by determining the stiffness of the material over range of temperatures or frequencies. I'hc essential components include an elcctro,ncchanical drive unit, a device for measuring displacement, an environmental chamber to facilitate heating and cooling of the sample, an electronics unit to control and process the measurement signals and various sample holding devices (otherwise known as frames and clamps).

The measurement of stiffness is achieved by imposing a small, well defined deformation on the sample and then sensing the displacement and phase shift between the displacement and applied i:'orcc.

I'he results given by this equipment allows users to obtain information concerning tle scoclastic behaviour, damping characteristics and thermal behaviour of the sample being examined.

According to the present invention, there is provided a device for holding samples such as powders, liquids, solid films, foams, bars or any other sample form of material in a manner different to c>;isting frames and sample clamps in a dynamic mechanical analyscr.

I'hc device normally comprises ol'a pocket lammed by folding usually, though not csclusively, a small piece of steel shim or other material around the sarnplc.

The pocket can either be open topped or not as required by the operator or as the sample dictates.

The pocket can also be formed with or without Ike inclusion ol'a tempcraturc sensor. lthe most common mode used to analyse a material is bending deformation.

Typically, a bar sample is supported by clamping across a fixed frame and then flexed from the middle or at one end whilst holding the outer sides or side rigidly.

The device described can be mounted in the instrument in place of a bar sample and utilising the bending deformation mode, though alternative mounting methods may als'bc employed.

I'hc invention comprises of a pocket of an inert material. usually steel, that is produced around the sample. The pocket so formed may or may not fully enclose the material that is being analysed cmd may or may not include a temperature sensor.

Figure t shows a pocket mounted in position inside a dynamic mechanical analyser.

Figure 2 shows a pocket fully formed with a contained test sample but not mounted in the dynamic mechanical analyscr Figure 3 shows a pocket with a sample powder inside prior to being closed to secure the test sample.

Figure 4 shows a pocket prior to folding into a Trough' ready to accept a test sample.

Claims

]. A device that can enclose, support and hold powders, liquids, thin films, bars, foam samples or any other sample form for analysis in a dynamic mechanical analyser.
2. A device that can fully seal and protect the sample from the surrounding environmcut prior to and during the perforrnancc of dynamic mechanical analysis.
3. A device that facilitates sample mounting for any automated handling or robotic system.
4. A device that can hold both sample and temperature probe in close proximity within the analytical chamber of a dynamic mechanical analyser.

lcferring to the drawing; attached, the pocket comprises oLa material such as a steel shim as shown in Figure 1. It is useful, though not essential that the mid line of the shin1 is scored or etched to aid folding along the mid line (1).

The shim is folded (as shown in Figure 2) and the test sample material is placed in the trough as shown (2). If required, a temperature sensor is placed in the trough, prior to closure of the pocket (3).

1'hc pocket is then closed as shown in Figure 3 and may if required he welded or sealed around the edges (4) to prevent ingress of air or humidity.

l'he pocket (6) is then mounted in the analytical fixture (I) of the dynamic mechanical analyser or similar stiffness measurement device, as shown in Figure 4. The poclct is usually, though not exchsivcly mounted using a bending configuration (7).