engineering thermoplastics | Innovation
Right: BASF is extending its Ultradur HR hydrolysis
resistant PBT product line with new E&E grades for demanding enclosure
applications
nent safety and has high melt stability for better processing. The new Crastin HR HFS family is claimed to allow designers to make components with thinner walls and allow processors to use newer technology as the material stays in the melt state longer. “This second generation of hydrolysis resistant
Crastin retains its high performance but processes like a standard Crastin grade,” says Antonio Nerone, Global Segment Leader Electric & Electronic, DuPont Perfor- mance Polymers. Crastin HR HFS is targeted for automotive electric
and electronic components and for hybrid and electric vehicles. It is already being used in high voltage shield connectors for battery packs and inverters. The family includes impact modifi ed grades with 15 and 30% glass reinforcement. Not to be left out of the party, Lanxess also has
hydrolysis-resistant grades of PBT, Pocan HR. In the USCAR Class 5 test, Pocan B 3233 HR retains around 80% of its original fl exural strength and more than 50% of its initial impact strength, says Dr Timo Immel, Pocan product development expert. Lanxess is expanding its range. Pocan B 3216 HR, for
example, has 15% glass fi ber reinforcement, and Pocan BF 4232 HR is a fl ame-retardant grade with 30% glass that has a V-0 rating at 0.4 mm. Unreinforced material grades and a variant with 45% glass fi ber content are also available on request. DSM says Arnite A HR is the fi rst high performance polyethylene terephthalate (PET) engineering plastic that is highly resistant to hydrolysis. It describes this as a breakthrough development that opens up opportuni- ties for use in automobile under the hood where it can offer signifi cant weight and cost benefi ts over metal. “Injection molded parts from conventional PET lose as much as half of their tensile strength after 1000 hours at 85°C and 85% relative humidity,” says Wouter
Gabrielse, Automotive Segment Manager for DSM. “Parts made from Arnite A HR keep around 90% of their initial strength under the same conditions.” He calls the performance “spectacular.” Arnite A HR grades are available in 35% and 50% glass fi ber reinforcement. Grades are being targeted at a variety of automotive under-the-hood applications, including throttle valve bodies, sensors, air control valve hous- ings, electronic throttle control (ETC) and exhaust gas recirculation (EGR) covers, and ignition systems.
Acetals advance
Celanese (which recently dropped the Ticona brand of its engineering materials subsidiary) has introduced several new acetal copolymer grades in the past few months. Hostaform XGC is a glass-reinforced grade, for example. Celanese already has glass-reinforced acetals in its portofolio, but they have mechanical properties inferior to those of reinforced PBT and polyamides. The company set itself the goal of developing compounds with mechanicals at least as good as these rivals, says Joachim Floeck, Celanese POM product marketing manager Europe. Its aim was to target applications such as gear housings, levers, sliders, and other highly loaded structural parts.
Figure 1: Durethan BKV60XF 60% glass reinforced PA6 from Lanxess shows better fl ow than its established easy-fl ow BKV60EF grade (melt viscosity at 280°C)
34 INJECTION WORLD | November/December 2013
According to Floeck, it has succeeded in this thanks to modifi cations to the polymer itself and to the additive package that improves coupling with the glass. He describes strain at break as “outstanding” and says toughness is much better than PBT (although still not as good as a polyamide). Parts display less anisotropy than earlier grades, although Floeck admits that it is not entirely clear why this is so. The new series includes two core grades: XGC10 and XGC25, 10 and 25% short glass fi ber reinforced, respectively.
Source: Lanxess
Acetal has an advantage over PBT in that its mechan- ical properties do not change at ambient temperatures.
www.injectionworld.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68