Search

BR-112022005584-B1 - COMPOSITION, RETICULATED COMPOSITION AND ARTICLE

BR112022005584B1BR 112022005584 B1BR112022005584 B1BR 112022005584B1BR-112022005584-B1

Abstract

COMPOSITION AND ARTICLE. This is a composition comprising the following: a) a first non-conjugated ethylene/alpha olefin/polyene interpolymer having a Mooney viscosity of 50; b) a second non-conjugated ethylene/alpha olefin/polyene interpolymer having a Mooney viscosity of 50; c) a calcined filler formed from a filler composition comprising kaolinite.

Inventors

  • Varun Thakur
  • Xiaosong Wu
  • Colin Li Pi Shan

Assignees

  • DOW GLOBAL TECHNOLOGIES LLC

Dates

Publication Date
20260310
Application Date
20200921
Priority Date
20190924

Claims (8)

  1. 1. Composition, characterized in that it comprises the following: a) 16.0% by weight to 20.0% by weight, based on the weight of the composition, of a first non-conjugated ethylene/alpha-olefin/polyene interpolymer having a Mooney Viscosity (ML1+4, 125 °C) measured in accordance with ASTM D-1646 > 50; b) 7.0% by weight to 9.0% by weight, based on the weight of the composition, of a second non-conjugated ethylene/alpha-olefin/polyene interpolymer having a Mooney Viscosity (ML1+4, 125 °C) measured in accordance with ASTM D-1646 < 50; c) a calcined filler formed from a filler composition comprising a kaolinite and a silica, wherein the weight ratio of the calcined filler to the composition is 0.25 to 0.30.
  2. 2. Composition, according to claim 1, characterized in that it also comprises carbon black.
  3. 3. Composition according to claim 2, characterized in that the weight ratio of carbon black to calcined filler is < 1.00.
  4. 4. Composition, according to any one of claims 1 to 3, characterized in that it has a Rheology Ratio (RR) (V0.1 (0.1 rad/s, 190°C)/ V100(100 rad/s, 190°C)) > 40.
  5. 5. Composition, according to any one of claims 1 to 4, characterized in that the second non-conjugated ethylene/alpha-olefin/polyene interpolymer has a Mooney viscosity (ML1+4, 125 °C) measured in accordance with ASTM D-1646 of 28 to < 50.
  6. 6. Cross-linked composition, characterized in that it is formed from the composition as defined in any one of claims 1 to 5.
  7. 7. Article, characterized by comprising at least one component formed from the composition as defined in any one of claims 1 to 5.
  8. 8. Article according to claim 7, characterized in that it is an extruded article, an injection-molded article or a thermoformed article.

Description

Cross-referencing related requests [0001] This application claims priority benefit from U.S. Patent Application 62/904,940, filed September 24, 2019, which is incorporated herein by reference in its entirety. Background of the invention [0002] Stricter carbon emission regulations are driving automotive manufacturers to reduce vehicle weight wherever possible. For example, in Europe, the emissions target will decrease from “125 g CO2 per km” to “95 g CO2 per km” by 2020. In modern vehicles, steel door panels are being replaced with aluminum/magnesium (Al/Mg) alloys to achieve significant weight reductions. However, the change from steel to an Al/Mg alloy (or just Al and Mg) has a significant impact on the rubber sealing profiles used to seal, for example, door and window panels to other surface components. Such profiles require much higher electrical resistivity (> 108 Ω^cm) compared to traditional profiles (around 106 Ω-cm). [0003] Traditional profiles formed from EPDM-based elastomer compositions have high carbon black content, which tends to aggregate to form conductive 3D networks within the final rubber formulations. Thus, there is a need to reduce the amount of carbon black to reduce the conductivity of the rubber. An insulating white filler can be used to replace some of the carbon black. However, the use of a white filler can have an adverse effect on the mechanical properties of the rubber, such as compression set and elasticity, and can create an increase in porosity in an extruded profile. An increase in the white filler content and a decrease in the carbon black content also affect the curing properties. There is a need for elastomeric compositions that provide high volume resistivity and excellent mechanical properties, and that can form extruded profiles with good integrity and minimal or no porosity. [0004] V. Krmelová et al., Evaluation of Effect of White Fillers on Selected Properties of EPDM Blend, Procedia Engineering, 136 (2016), 336 to 340, discloses EPDM compositions containing various white fillers. These blends exhibit relatively low volume resistivities (< 3.48 x 10⁷ Ω^cm, see Table 4), which are too low to meet the current requirement of “> 10⁸ Ω^cm”. U.S. Patent 9,994,095 discloses a caulking strip for an automobile. The caulking strip design uses a non-electrically conductive material to help prevent the formation of an electrical circuit caused by snow or water intrusion (see Abstract). This patent generally discloses the use of a rubber material, such as an EPDM sponge or a solid EPDM rubber material. Carbon black can be used to adjust the electrical resistance of EPDM rubber (see column 6, lines 28 to 41). [0005] The POLESTAR 200R Product Guide (The Application of Mineral Science, POLESTAR 200R in Rubber, 2017) discloses a cable formulation that contains, in part, VISTALON 4608 and POLESTAR 200R. Although the formulation shows a relatively high volume resistivity (1.3 x 1014 Ω^cm), the elongation at break is relatively low (240%). See also the POLESTAR 200R Product Guide (The Application of Mineral Science, Calcined Clay in EPDM Rubber, 2018). H. Oggermüller, Gummi Fasern Kunststoffe, 56, 1, 2003, 31-37 (English Abstract), discloses EPDM formulations containing reduced levels of carbon black and different mineral fillers, selected from silica, calcium carbonate, talc, and kaolin. This reference reveals that only silica-reinforced EPDM formulations showed good extrusion and sufficient mechanical and electrical properties. [0006] As discussed above, there remains a need for elastomer compositions for automotive parts that provide high bulk resistivity and excellent mechanical properties, such as elongation and compression set, and provide good processability and curing properties. Such compositions must form good extruded profiles with minimal or no porosity. These needs have been met by the following invention. Summary of the invention [0007] This is a composition comprising the following: a) a first non-conjugated ethylene/alpha-olefin/polyene interpolymer having a Mooney viscosity > 50; b) a second non-conjugated ethylene/alpha-olefin/polyene interpolymer having a Mooney viscosity < 50; c) a calcined filler formed from a filler composition comprising kaolinite. Detailed description of the invention [0008] Elastomeric compositions have been discovered that possess excellent bulk resistivity, excellent elongation and compression set, and have good rheological and curing properties. These compositions can be used to form extruded profiles with minimal or no porosity. As discussed above, the composition comprises the following: a) a first non-conjugated ethylene/alpha-olefin/polyene interpolymer having a Mooney viscosity > 50; b) a second non-conjugated ethylene/alpha-olefin/polyene interpolymer having a Mooney viscosity < 50; c) a calcined filler formed from a filler composition comprising kaolinite. [0009] In one embodiment, or a combination of two or more embodiments, each desc