Polyamide improves connector performance

A DSM Engineering Plastics product story

Edited by the Engineeringtalk editorial team Jan 6, 2006

Electronics manufacturer Tyco Amp Den Bosch has changed the material it uses for moulding PCMCIA card headers from liquid crystal polymer to Stanyl polyamide 4,6.

Electronics manufacturer Tyco Amp Den Bosch has changed the material it uses for moulding PCMCIA (PC card) headers from liquid crystal polymer (LCP) to Stanyl polyamide 4,6 (PA46), gaining overall cost savings, better mechanical properties, and very low warpage.

Stanyl grade 46HF 5040, a high-flow formulation, easily meets the flow properties of LCP, allowing ready moulding of the tiny features in the header while enhancing much needed mechanical properties.

PC cards are often used in portable and laptop computers to provide plug-in expansion, network connectivity, telecommunications modems, and a host of addon functions developed over many years.

Very low warpage, dimensional stability and high strength are critical to the application, as the slim cards are produced to very high dimensional tolerances and feature locating keys under 1mm thick.

The header must securely hold 68 pins with a pitch of 0.6mm - a little more than half a millimetre apart - and stand up to often rough card insertion practices of portable computer owners.

In addition, the heat resistance of Stanyl fits within the production processes of the laptop mainboard, which requires lead free soldering of surface-mount electronic components.

The header design adds complexity in that it incorporates card slots extending several centimetres out from the header itself.

Such a design saves assembly labour but adds moulding challenges, made even more challenging by the minuscule dimensions of the moulded features.

Model variations include single-card and dual-card headers.

"We worked with Tyco particularly to reduce rejects due to warpage", said Patrick Duis, Application Development Manager, Connectors, DSM Engineering Plastics.

"Stanyl High Flow enables consistent production of the highly detailed part, and we were able to help Tyco achieve lower per-part cost".

Stanyl High Flow grade 46HF 5040 is one of the Stanyl family of heat-resistant polyamide moulding compounds, produced and marketed exclusively by DSM and available worldwide.

Stanyl is used in demanding applications in the automotive and electrical and electronics industries, as well as many other applications.

Stanyl is offered in a wide variety of grades including high-flow, abrasion-resistant, and unfilled (nonreinforced), as well as grades containing glass fibres, minerals, lubricants, impact modifiers, or flame retardants.

Higher crystallinity and a faster rate of crystallisation give Stanyl a technical edge over such engineering plastics as PA6, PA66, polyesters, and other high heat-resistant resins such as semi-aromatic polyamides (PPAs), PPS and LCPs.

compared with these, Stanyl grades show better heat resistance, mechanical properties at elevated temperatures, wear and friction behaviour and, with faster cycle time and increased flowability, improved processing economics.

A dedicated staff of DSM specialists provides technical support in design, moulding and material selection of Stanyl.