TPEs | Innovation
Figure 2: Basic properties of Sarlink TPE injection moulding grades from Teknor Apex
Sarlink® Compounds High
Performance Property Specific gravity
Hardness, Shore A (5 sec.) Tensile strength, MPa Ultimate elongation, % 100% modulus, MPa Tear strength, kN/m
1.04 65
6.7
780 2.0
28
20 39
0.92 64
4.9
417 2.3
23
20 35
231
General- Purpose
Test Method TPE-S TPV TPE-S TPV ISO 1183 ISO 868 ISO 37 ISO 37 ISO 37
1.20 62
5.1
750 1.8
ISO 34-B angle,
500mm/min
Compression Set 22 hrs @ 23 ºC ISO 815 22 hrs @ 70 ºC Type A
Apparent shear viscosity, Pa.s. Source: Teknor Apex
variety of custom-matched colours, and they generally do not require pre-drying. On the other hand, the company says, TPVs exhibit better resistance to oil and grease and have a higher service temperature – around 115°C as against 100°C for TPE-S compounds. Teknor Apex divides the injection moulding grades in
Right:
Multibase sees great potential for its TPSiV products in applications such as smart watches
the new range into two: high performance and general purpose. The former, mainly aimed at exterior applica- tions, have hardnesses ranging from 55 to 70 Shore A. They have a broad processing window, exhibit smooth surfaces, and provide high UV stability and heat resistance. General-purpose injection moulding compounds for under-hood and interior components go from 40 Shore A to 50 Shore D. These compounds also have a broad processing window and exhibit relatively low odour and fogging. Italian compounder So.F.Ter is promoting a two-
component injection moulding solution for automotive soft-touch interiors, based on a glass-reinforced polypropylene compound overmoulded with its Laprene 8ST.A80 SEBS-based TPE. The SmarTouch 2K solution “combines aesthetics, ecology and convenience,” according to So.F.Ter. The company cites very good fogging performance, complete recyclability and low weight at a competitive cost. The two compounds used in the SmarTouch 2K
concept have a high chemical affinity, “which not only ensures their perfect adhesion, but also makes it possible to recover and recycle the vehicle panels at the end of the life cycle,” says So.F.Ter. “The granulate obtained by grinding the SmarTouch 2K panels and
20 INJECTION WORLD | April 2014
ASTM D 3835 110 TA Procedure
24 38
120
23 34
310 22 5.4
270 3.8
32
0.95 65
production scraps is a polyolefin compound with good impact resistance and can be reused for the production of other components.” Laprene 8ST.A80 has a density of 0.91 g/cm3
, so
panels are lighter than those made using alternative systems based on polar polymers such as TPU (basic performance data is shown in Figure 3). SEBS is also rather cheaper than TPU. Laprene 8ST.A80 also passes all the tests covered by Volkswagen’s 50180 norm governing fogging. After seven days of exposure to heat (85°C), there is only a negligible change in colour and mechanical properties. And the TPE passed Fiat’s M700 scratch resistance test and LP-463 P chemical resistance test. PolyOne GLS Thermoplastic Elastomers unveiled its
Versaflex CE thermoplastic elastomers for applications in the consumer electronics market last year. The company is targeting such applications as electronic wristbands, smart watches and mobile devices. It says the portfolio of standard and custom-formulated TPEs offers designers a combination of performance, visual appeal and physical aspects. “Designers can combine outstanding aesthetics, such as silky-smooth soft feel, with colour and texture,” the company says. The grades also provide very good chemical and UV resistance. While not providing detailed information, the
company claims that the Versaflex CE range “incorpo- rates new TPE technology that addresses several top challenges, including desirable haptics for high-end phone and tablet cases and excellent vibration-damping properties to improve device performance and comfort in use.” It says the range includes products based on different blends of technologies designed to draw on GLS’s “chemistry agnostic” approach to leveraging its strong supplier relationships and using the chemistry most suited for the application. Versaflex CE grades can bond to PC/ABS and other substrates during moulding. Not surprisingly, other
TPE suppliers are after the portable electronics market, too. Multibase, a business unit of Dow Corning, has targeted the sector with its range of thermoplastic silicone vulcanizates, or TPSiVs. Mehdi Abbadi, head of marketing for Dow Corning in Europe, highlights the ability of the company to create compounds compatible with a wide range of thermoplastics by changing the thermo-
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 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76