Fingerprinting Glass Reinforced Materials

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Every plastic material has a unique performance “fingerprint” that identifies not only the polymer type but reinforcement level as well.  AGS Technology’s raw material testing laboratory has the equipment and skilled personnel to run and analyze the corresponding battery of tests to help solve plastic material identification and performance on a daily basis.

For glass reinforced plastic materials the following three lab tests will help provide the initial positive identification:

Specific Gravity (ASTM D792-A / ISO 1183-1):  A dimensionless quantity defined as the ratio of the density of a given material to the density of water. AGS performs the test by weighing a small piece cut from a dry as molded tensile bar and then submerging the same piece in 23.0°C distilled water and then re-weighing while it is completely submerged. The specific gravity is calculated from the weight difference.

Ash Content (ASTM D2584 / ISO 3451-1):  An Ash Content test is used to determine if a material is filled. The test will identify the total filler content. The test involves taking a known amount of sample, placing the weighed sample into a dried / pre-weighed porcelain crucible, burning away the polymer in an air atmosphere at temperatures above 500°C, and weighing the crucible after it is has been cooled to room temperature. Ash residue remaining in the crucible is considered filler as a percentage of the total sample.

Tensile Strength (ASTM D638 / ISO 527-1):  Tensile strength is a measure of a materials ability to resist being pulled apart. Testing is carried out on a universal testing machine using dry as molded test bars. The test bar is gripped between a fixed and moveable crosshead. The moveable crosshead is made to travel at a constant rate until breakage occurs. The testing machine is equipped with sensors to measure the stress being exerted on the specimen. Tensile strength is calculated by dividing the cross sectional area of the test bar by the maximum force recorded by the load cell.
Once accurate test results are generated, these can be compared to the AGS database matrix to help generate an initial match.

Specific Gravity 1.14 1.36 1.54
Ash Content 30% 30% 30%
Tensile Strength 9,000 psi
(62 MPa)
22,000 psi
(152 MPa)
15,000 psi
(103 MPa)
Material Match 30% Glass PP 30% Glass PA66 30% Glass PBT
Specific Gravity 1.05 1.22 1.25
Ash Content 20% 13% 10%
Tensile Strength 7,500 psi
(52 MPa)
15,000 psi
(103 MPa)
9,000 psi
(62 MPa)
Material Match 20% Glass PP 13% Glass PA66 10% Glass PC

From here, additional viscosity, impact, flexural, heat, environmental, etc…testing will be needed to fully identify and formulate it into its highest value application.