Multimodal polymer composition
US6185349A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 3, 1999 |
| Grant date | Feb 6, 2001 |
| Priority date | — |
| Expiry date | Mar 3, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/4407
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A multimodal polymer composition for fiber optical cables and a fiber optical cable comprising the composition are disclosed. The composition is characterized in that it comprises a multimodal polyethylene with a density of 0.920-0.965 g/cm.sup.3 and a viscosity at a shear stress of 2.7 kPa (.eta..sub.2.7kPa) of at least 150 kPa.s, said multimodal polyethylene comprising a low molecular weight (LMW) ethylene homo- or copolymer fraction and a high molecular weight (HMW) ethylene copolymer fraction, said multimodal polymer composition having a weight ratio of the LMW fraction to the HMW fraction of (35-55):(65-45). Preferably, the multimodal polyethylene is a bimodal polyethylene and has a shear thinning index (SHI), defined as the ratio of the viscosities at shear stresses of 2.7 and 210 kPa, respectively, of SHI.sub.2.7/210 =20-150. Also, preferably, the multimodal polyethylene has a MFR.sub.5 of 0.1-2.0 g/10 min and a melt strength at 190.degree. C. of at least 4 g. The multimodal polymer composition is particularly useful as a material for slotted core elements of fiber optical cables of the slotted core type.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.