Melt Flow Analysis

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Melt Flow Analysis

Abstract:
Polyethylene’s melt flow properties at 190°Cwere identified through the use of an extrusion plastometer. The data obtained was used to determine the average melt flow rate and melt flow index. Introduction:

Polymers are an important class of materials. The range of properties of polymeric materials allows it to be essential in everyday life. The simplest polymer is polyethylene which consists of long chains of C2H4 monomers. Each monomer is joined by a covalent bond while the bonding between the chains is a weak van der Waals bond. The weakness of the van der Waals bond is the source for the properties of polyethylene. An extrusion plastometer will be used to measure the characteristics of polyethylene to ensure a quality product. The flow rate of polyethylene will be calculated by extruding the polyethylene through a die at a specific temperature and pressure. The data can be compared with given values to meet the standards of a quality product. Experimental Procedure:

The extrusion plastometer was preset to a temperature of 190°C, and inserted with a die. 7 grams of polyethylene was obtained. After the extrusion plastometer reached 190°C, the polyethylene was added into the heat chamber of the extrusion plastometer in increments. A plunger was used to compress the polyethylene as it melted. The polyethylene was heated for about 15 minutes. A 9.900 kilogram mass was then added to the plunger to apply more pressure. The extruded polyethylene was cut and weighed at 30 second intervals. A total of 5 samples were collected. Results and Discussion:

Sample| Time (s)| Mass (g)| Accumulated Mass (g)|
1| 30| 0.96| 0.96|
2| 60| 1.01| 1.97|
3| 90| 0.98| 2.95|
4| 120| 1.04| 3.99|
5| 150| 1.29| 5.28|
Table 1

Graph 1

Graph 2
From Table 1, the total mass is 5.28 grams, and the total time is 2.5 minutes. The average flow rate can be computed with this data. Average flow rate: 5.28 grams2.5 minutes...
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