General properties of Stanyl®

Stanyl is an aliphatic polyamide formed by the polycondensation of 1,4-diaminobutane and adipic acid (see figure below).

Differences in the structure of polyamides.

Although there are similarities between the molecular structure of Stanyl and that of PA66, the higher number of amide groups per given length of chain and the more symmetrical chain structure of Stanyl result in a higher melting temperature 295°C (560°F), a higher crystallinity, and faster crystallization (see table below).

Typical properties based on structure.

The crystallinity of Stanyl is approximately 70%, compared with 50% for PA66. This results in a high heat distortion temperature of 190°C (375°F) for unreinforced Stanyl and 290°C (555°F) for glass fiber reinforced Stanyl. These features give Stanyl a technical edge over engineering plastics like polyamide 6 and 66, polyesters, and semi-aromatic polyamides (PPAs) with regard to heat resistance, mechanical properties (including creep and fatigue) at elevated temperatures, wear and friction behavior and, due to an advantage in cycle-time, economical processing.

Stanyl properties
The excellent properties of Stanyl lead to important advantages for the customer such as cost reduction, longer lifetime, and high reliability. Stanyl provides the performance of high heat resins such as LCP, PPS, and even PEEK with the ease of processability and design usually found with standard engineering plastics.

Benefits for both molders and end users include:

• High temperature resistance for under the-hood durability and lead-free solder processing capability
• Excellent chemical resistance that helps increase lifetime of application
• Longer lifetime and higher reliability of parts due to low creep, excellent fatigue behavior, and low wear
• Excellent mechanical properties allow for thinner walls which lead to weight reduction and lower part prices
• 30% productivity increase of molding equipment based on cycle time alone (productivity achievable through increase of number of cavities due to high flow behavior)
• Greater design freedom due to the combination of excellent mechanical properties and good mold-flow behavior
• Ability to consistently fill very thin-walled products enabling the most advanced products to be molded effortlessly
• Use of regrind up to 25-50% possible without significant loss in properties (economical benefit while maintaining product reliability)
• Economical, safe, and convenient processing due to the use of 80°C (175°F) water-heated molds
• No post-treatment due to absence of flash
• No retooling necessary when switching from PA6, PA66, or polyesters when rising temperatures require a higher heat resistant material

Tensile strength versus tensile modulus of Stanyl.

Stanyl product scope
Stanyl is offered in a wide variety of grades including unfilled (non-reinforced), as well as grades containing glass fiber, mineral, lubricants, and/or flame retardants.  A list of the most important grades can be found in the table below.

Stanyl product portfolio.