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Comparing long term multi-temperature flexural creep with DMA TTSP techniques for neat PP and PP-GF30 long fiber thermoplastic


Title: Comparing long term multi-temperature flexural creep with DMA TTSP techniques for neat PP and PP-GF30 long fiber thermoplastic

Authors: Max R. Kauphusman, Regan G. Harvey, Eric O. Kerr-Anderson

DOI: 10.33599/nasampe/c.23.0146

Abstract: The long-term behaviors of a material, such as creep, are an important consideration when designing for longevity, particularly when using thermoplastics. The use of semi-crystalline thermoplastics and fibers can mitigate the effect of creep. Analysis for different combinations of matrix, fiber, fiber length, and fiber volume fraction has created a potentially very large testing need for long fiber thermoplastics (LFT) potentially used in more demanding service conditions. Furthermore, creep testing is one of the most expensive datasets to acquire in both cost and time commitment. Creep is typically analyzed for materials by varying loads and temperatures. Dynamic Mechanical Analysis (DMA) offers a unique opportunity to characterize creep properties of polymers in a relatively short period of time using a technique called Time Temperature Super Positioning (TTSP). TTSP works by holding either frequency or loading constant at set temperatures for a constant period of time. WLF equations are then used to combine the curves of several trials at different temperatures into a master curve which can be used to extrapolate creep performance at designated reference temperatures. This method will save considerable time if results are comparable to actual creep. Methods were examined to compare neat polypropylene and PP-GF30 long fiber thermoplastic. Long-term flexural creep was also tested at multiple loads and temperatures. Results from TTSP method were compared to those of long-term tests.

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Conference: CAMX 2023

Publication Date: 2023/10/30

SKU: TP23-0000000146

Pages: 13

Price: $26.00

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