SILTEM

Product Pebax Pebax Pebas Grilamid Ely 60 Siltem ... 

PEI polymers exhibit minimal creep underload. Eor example, unreinforced Ultem 1000 maintains part dimensions over thousands of hours at room temperature at a loading of 34 N/mm (4930 psi). PEI resins are available with HDTs ranging to 220°C (Ultem 5000). PEI copolymers with siUcone mbber allow for flame-retardant, high temperature appHcations such as plenum wire coatings (Siltem). Reinforcement of PEI resins improves their temperature performance. Table 13 compares unreinforced and 20% glass-reinforced Ultem resins. 

Also of interest is the polysiloxane-polyetherimide copolymer marketed as Ultem Siltem STM1500, which is considered further in Chapter 29. 

These materials are developed from the polyetherimides introduced by General Electric (see also Section 18.14.2). At the time of writing one grade, Ultem Siltem STM 1500, is being offered. It is of particular interest as a material for wire and cable insulation, as it not only has excellent flame resistance coupled with low smoke generation but also avoids possible toxic and corrosion hazards of halogenated polymers. This can be of importance where there are possible escape problems in the event of a fire, such as in tunnels, aircraft and marine (particularly submarine) vessels. 

Table 29.6 Some typical properties of a polysiloxane-polyetherimide copolymer (Ultem Siltem STM 1500)...

Hydel, Lubricomp, RTF, Siltem, Stat-Kon, Tempalux, Ultem. 

Product Pebax 2533 Pebax 4033 Pebas 6333 Grilamid Ely 60 Siltem STM1500... 

Siltem . [GE Plastics] Silicone/poly-etherimide copolymer for combustion corrosion-sensitive applies., cable insulation. 

Poly(dimethyl siloxane) surfactant, 322 Siltem STM 1500 Poly(ether imide), 230 Sintimid ... 

By carefully adjusting block size and comonomer composition, J. Celia at General Electric developed a series of thermoplastic silicone-polyimides (7) with excellent electrical and thermal properties as well as low smoke generation [29], These materials are marketed under the name Siltem as wire coatings and enamels, and can be found in a variety of aerospace applications including passenger aircraft. 

Siltem Siloxane-etherimide copolymers and blends GE Plasties... 

SILTEM (GE) Poly(etherimide) Polysilicone Fire resistant. Very high cost... 

A PEI resin blended typically with a sulfone resin can yield a material with high heat resistance, high mold flow, and low smoke generation. These are often called PEI copolymers by SABIC Innovative Plastics. SABIC s Siltem PEI-siloxane resin is a block copolymer of PEI and polysiloxane. 

Ultem and Siltem resins products and markets guide. SABIC Innovative Plastics 2008. 

Modification of PC by copolymerization has been highly successful, resulting in six commercial products with others in development. It seems that the strategy was extended to PEI, creating amorphous siloxane-poly-etherimide copolymer (Si-PEI), SILTEM (see Fig. 2.4), with Tg = 202°C, 400% elongation at break, flexibility, excellent mechanical performance. 

Comments GF = glass fibre, PEI/PC = blend, SILTEM = coatings. flexibie siloxane-polyetherimide copolymer for cable and wire ... 

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