EuroWire July 2022

Technical Article

The future of Estane non-halogenated flame-retardant thermoplastic

polyurethane By Nico Rems, Lubrizol Engineered Polymers

hardness of this product range goes from 80 to 95 Shore A and all grades are polyether-based aromatic TPUs, which are regulatory compliant. 1.1.1 Legacy product portfolio Estane ZHF 90AT2 NAT 055, Estane ZHF 58202 NAT 02, Estane ZHF 90AT8H NAT 02, Estane ZHF 58211 NAT 01, Estane ZHF 85AT8 MATT 01 and Estane ZHF 85AT8 NAT 01. 1.1.2 New developments Estane ZHF 95AP7 NAT 01, Estane ZHF 92AM9 NAT 01, Estane ZHF 58370 NAT 01, Estane ZHF 80AT7 NAT 01, Estane ZHF 88AT8 NAT 01, Estane EV 89AT9 NAT 01, Estane EV 90AT2 NAT 02 and Estane EV 88AT2 NAT 01. 1.1.3 Breakthrough grade Estane ZHF 90AM9 NAT 01, which will be discussed in depth in the last chapter of this article. The product overview, properties, features and applications of the main grades can be found in Table 1 . 2 Estane NHFR compounds highlighted for cable applications 2.1 For FT-2 small diameter cables: Estane ZHF 90AT2 NAT 055 Plasticiser-free Estane ZHF 90AT2 NAT 055 TPU has a UL-94 V2 rating and an oxygen index around 24 per cent. This grade is specially formulated for cable jacketing of automation cables that need to pass UL 1581 FT-2 with a small diameter (ø4.3mm) and PE insulation. Other flame-retardant test capabilities with proven track records are automotive ISO 6277 FR and IEC 60332-1-2. It exhibits good surface aesthetics. 2.2 For fibre optic cables: Estane ZHF 58202 NAT 02 Estane ZHF 58202 NAT 02, with a UL-94 V2 rating and an oxygen index of 25 per cent, is suitable for application in optical fibre cables with its favourable low COLTE (coefficient of linear thermal expansion). This material exhibits easy processability and surface aesthetics. Regulation-wise, it has global compliance and a UL 105°C temperature rating can be achieved. This grade also exhibits easy colourability. 2.3 For highly demanding cable flame requirements: Estane ZHF 90AT8H NAT 02 Estane ZHF 90AT8H NAT 02 is a TPU with a UL-94 V0 yellow card and a 24 per cent oxygen index. This grade combines VDE 282 and UL1581 suitability and can pass more stringent UL1581 FT-1, VW-1 and UL 1061 cable-flame tests on medium to large diameter cables in drag chain, sensor, data cables and others. It achieves a UL temperature rating of 105°C. It exhibits excellent/easy processability and surface aesthetics, and regulation-wise, it has global compliance.

Introduction The importance of flame retardants in the plastics industry continues to grow. Higher performing materials are meeting increasingly stringent legislation, and environmental pressures in certain regions are driving flame retardant producers to offer solutions using a wide range of chemistries. Interest in non-halogenated flame retardants to replace haloge- nated flame retardants is greater than ever, particularly in Europe due to the upcoming ban of certain halogenated additives used in halogenated, flame-retardant TPU compounds. Halogen-free technology has been evolving for more than 20 years, but it has only gained significance recently. It developed from a marketing concept to a real market due to new NHFR technologies. Today, NHFR products offered can now meet customer requirements more than ever. Due to this trend in the market, Lubrizol Engineered Polymers started a centre of excellence based in Oevel, Belgium, focusing on developing the most optimum NHFR thermoplastic polyurethane portfolio. This article highlights the properties and typical end uses of some particular commercial non-halogenated flame-retardant TPU grades, and outlines the features of a new high-performing NHFR TPU development called Estane ZHF 90AM9 NAT 01. 1 Overview of Estane flame-retardant commercial products and new developments 1.1 Estane non-halogenated flame-retardant TPU compounds The Estane NHFRTPU portfolio can be divided into three categories: the legacy product portfolio; new developments from last year; and the new breakthrough grade Estane ZHF 90AM9 NAT 01. The Thermoplastic polyurethane compounds have been used in cable jacketing for their flexibility, durability and low-tem perature performance for decades. The first non-halogenated flame-retardant (NHFR) thermoplastic polyurethanes (TPUs) were developed and commercialised by Lubrizol Engineered Polymers nearly 40 years ago. Interest in NHFR TPU com pounds has gained momentum recently. To be aligned with market needs, Lubrizol has developed a broad portfolio of NHFR TPU compounds commercialised as Estane® ZHF TPU. This article highlights the properties and typical end uses of some of these grades and outlines a new high performing, zero-halogen, flame-retardant (FR) TPU compound.

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July 2022