An Investigation of Friction and Wear Behaviors of Polyimide/Attapulgite Hybrid Materials

Abstract

Summary: PI/AT hybrid materials were prepared by blending of poly(amic acid) and purified AT as a type of fibrillar clays. The friction and wear behaviors of the PI hybrids were evaluated on a ball‐on‐disc wear tester. The particle size of AT in the hybrid containing 5 wt.‐% AT was about 10–100 nm in diameter and 100–1 000 nm in length. Tensile tests on the PI hybrids showed that the strength and the toughness of PI/AT hybrid materials were improved simultaneously when the content of AT was less than 5 wt.‐%. The friction coefficient and wear rate of the PI hybrids first decreased and then increased with increasing content of AT. The wear rate of the hybrid containing 3 wt.‐% AT was more than 6 times lower than that of pure PI. SEM examination of worn surfaces showed that type of wear changed from adhesive wear of pure PI into abrasive wear of the PI hybrids with adding AT to PI matrix. Debris analysis suggested that AT as filler inside the PI matrix could prevent the formation of bigger debris and a chemical reaction that occurred during the friction process of pure PI but not in the hybrids.A plot of the calculated wear rate versus filler content.magnified imageA plot of the calculated wear rate versus filler content.

Palygorskite as an epoxy polymer reinforcement agent

“…Although palygorskite has been investigated as a reinforcement agent for several other polymer systems [11][12][13][14][15][16][17][18][19], the benefits seldom approach those observed for the soft polymer matrix standard in the present work. For instance, the tensile strength of polyethylene-palygorskite formed by in-situ polymerization was increased by a maximum of only 20% in comparison to the pristine polymer [15,16,19].…”

“…For the related polypropylene-palygorskite composite system, the clay served as a good nucleating agent for isotactic polypropylene, and the relative crystallinity and crystallization temperature of the composite materials generally increased with filler content [17]. An improvement of only 25% in mechanical properties was found for polyimide composites containing 5% palygorskite [13].…”

“…Nevertheless, owing to the relatively high surface area and lath morphology of these minerals, particularly in the case of palygorskite, they have found use as absorbents, pigments, catalysts, and rheological control agents [5,[7][8][9][10]. However, palygorskite has received relatively little attention as a polymer reinforcement agent with only a few studies being devoted to composites of polyolefins, polyurethane, polyimide, and polyamide [11][12][13][14][15][16][17][18][19].…”

Synthesis and properties of waterborne polyurethane/attapulgite nanocomposites

“…The smallest structure unit of AT is fibrillar single crystal with a length of several micrometers and 10-25 nm in diameter [11]. Although in recent years there have been some reports of the use of AT in polypropylene, Nylon 6, polyaniline, polytetrafluoroethylene, polyamide [12][13][14][15][16] and so on, AT has not received much attention as a filler for the enhancement of mechanical performance of polymers.…”

Polymer Nanocomposites with Thermoplastic Matrices—Processing and Tribology

“…Despite a great volume of research in the field of PCNs, only a few of the studies have considered their tribological behavior. [131][132][133] However, these PMs find wider and wider application in the automobile industry, as well as some other branches of engineering, where serviceability of the products depends on wear resistance and other friction parameters. [132,134] Research has indicated that the PM triboengineering properties can be increased by filling thermoplastics with organoclays and the friction behavior of nanocomposites is influenced by a number of factors, which should be considered when designing mix formulations.…”