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Polyamide Toughening
Polyamides are the most widely used engineering thermoplastic resins because of their value in delivering mechanical characteristics, such as good heat, abrasion and chemical product resistance to formulated compounds.
Nevertheless, in a growing number of applications where impact resistance is required and where brittleness causes major concerns, as well as in the demolding step of the injection molding process, improvements in performance properties are required.
To improve performance, grades in the Exxelor VA range can be added at different treat levels to polyamide matrices.
The performance of polyamide 6, polyamide 6,6 , polyamide 12 and other high temperature polyamides (e.g. PA 4,6, PPA, ...) can be increased by reactive extrusion with grades in the Exxelor VA range. The reactive toughening can give impact resistance to polyamides down to -40°C.
 | Ductility
Ductility down to -40° C
To get a very efficient reinforcement of the polyamide matrix, the grades in the Exxelor VA range can be added at levels of 15 to 20 % by weight, or higher, depending on the properties desired.
The inherent low glass transition temperature of Exxelor modifiers provides enhanced ductility down to very low temperatures.
With optimal dispersion during the compounding process, the rubbery Exxelor modifier phase acts as an effective stress concentrator leading to excellent impact properties.
 | Dispersion
With optimal dispersion during the compounding process, the rubbery Exxelor modifier phase acts as an effective stress concentrator leading to excellent impact properties.
 | Dry as Molded State
To avoid breaking thin sections of polyamide parts at the injection demolding stage, grades in the Exxelor VA range can be added at levels as low as 2-3% up to 8-9% in weight.
| Glass/Mineral Reinforced Polyamide
Grades in the Exxelor VA range, when added to glass fiber reinforced polyamide formulations, improve resistance to crack initiation and limit the crack propagation. Also enhanced is elongation which results in higher energy absorption. In such formulations, grades in the Exxelor VA range are typically added at levels of 6 to 12% by weight.
 | Processing
Exxelor modifiers are available as free flowing pellets. They are preferably blended with polyamide in twin-screw extruders. Single-screw extruders can also be used under certain conditions.
Injection molding and extrusion molding are the two most conventional processes used for the transformation of Exxelor modified polyamide compounds.
Blow molding technology is being optimized to polyamide blends for new automotive applications. Please contact your nearest ExxonMobil Chemical sales office to learn more of our development in the field of polyamide modifiers for blow molding applications.
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