Polymer Analysis of Fiberglass Reinforced Nylon-6 Pellets for Injection Molding

Project Overview: This polymer analysis project involved comparative analysis of two samples of black polymer pellets, supposedly 30% glass-filled Nylon-6, to assist an injection molder in understanding their properties before use. Samples A and B, believed to be similar, are shown in their as received state in Figure 1.

nylon 6 pellets for injection molding
Figure 1. Fiberglass Reinforced Nylon-6 Pellets with Sample A on the left and Sample B on the right. The scale bar is 0.5 inches.

FTIR Polyamide Analysis

The pellets were tested using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) to confirm their composition as Nylon-6. FTIR irradiates materials with infrared light to measure absorption characteristic of functional groups, finding specific chemical structures. ATR-FTIR, requiring minimal sample preparation, efficiently tests polymeric materials.

The ATR-FTIR spectra of the Nylon-6 30% fiberglass pellet Samples A and B are overlaid
Figure 2. The ATR-FTIR spectra of the Nylon-6 30% fiberglass pellet Samples A and B are overlaid

TGA Analysis

Thermogravimetric analysis (TGA) characterized the samples thermally, finding moisture, ash content, and fiberglass weight. Samples went through TGA from room temperature to 750 °C under various purge gases, testing decomposition stages and remaining fiberglass post analysis.

Figure 2. The TGA thermogram of the Sample A. The TGA was run as follows: 25 °C to 200 °C under N2 flow (10 mL/min) with a heating rate of 20 °C per minute and then, 200 °C to 750 °C under air flow (10 mL/min) with a heating rate of 30 °C per minute.
Figure 3. TGA thermogram of Sample A, showing moisture and fiberglass content.
TGA thermogram of nylon 6 sample with carbon black and glass fiber
Figure 4. TGA thermogram of Sample B, showing similar moisture and fiberglass content.
fiberglass remaining of nylon 6 after tga analysis

Figure 5. The remaining glass fibers after the TGA run.

DSC Polyamide Analysis

Differential Scanning Calorimetry (DSC) measured glass transition (Tg) and melting temperatures of the pellets. Heating from room temperature to 300 °C provided thermal profiles, showing differences between molecular weight and polymer chain characteristics between Samples A and B.

DSC thermogram of nylon 6 plastic
Figure 6. DSC thermogram of Sample A, showing Tg and melting temperatures.
dsc thermogram of nylon 6 polymer
Figure 7. DSC thermogram of Sample B, showing similar thermal characteristics.

HS-SPME-GC-MS Analysis

Head Space-Solid Phase Microextraction (HS-SPME) coupled with Gas Chromatography-Mass Spectrometry (GC-MS) analyzed volatile organic compounds in the pellets. This solvent-free technique identified organic components, including caprolactam, UV stabilizers, and aniline.

Head Space Solid Phase Micro-Extraction Gas Chromatography Mass Spectroscopy Analysis of Volatile Organic Components in Nylon-6 Samples

Polyamide Analysis Conclusions

This comprehensive polymer analysis provided insights into water content, nylon-6 resin properties, carbon black and fiberglass content, thermal behaviors, chain lengths, and volatile organic compounds present in Samples A and B.

Contact Us

For more information on polymer analysis or inquiries regarding our services, please contact us. We welcome discussions and collaborations related to plastic, nylon, and polyamide analysis.