ELASTOMER COMPOSITION INTENDED FOR EMBEDDING A COMPACT ANTENNA

Abstract

The subject matter of the present patent application constitutes an elastomer composition intended for embedding a compact antenna designed to be used and operated in close proximity with regard to the human body to build short-range wireless communication links.

The elastomer composition for embedding a compact antenna is based on natural rubber and components whose quantities are expressed in parts in wt per 100 parts by weight of natural rubber (phr), namely: sulfur1 to 2 phr; phenyl-trichloromethylsulfenyl-benzene sulfonamide0.1 to 0.5 phr; diphenylguanidinefrom 0.3 to 0.8 phr; tertiary butyl-benzothiazolyl-sulfenamidefrom 1 to 2 phr; dimethylbutyl-phenyl-p-phenylenediamine1.5 phr; polymerized trimethyl dihydroquinoline1.5 phr; stearic acid2.0 phr; zinc oxide3.0 phr; rapeseed oil15 to 30 phr; bis (triethoxysilylpropyl) tetrasulfide-silanefrom 0.1 to 4.0 phr; 3-thiocyanato-propyl-triethoxy silanefrom 2.0 to 6.0 phr; carbon black5.0 phr; optionally silicon dioxidefrom 10 to 50.0 phr, microcrystalline cellulosefrom 20.0 to 60.0 phr. The composition of the invention is multilayer.

The advantages that the composition intended for embedding a compact antenna provides are: high efficiency when the antenna is placed over or in close vicinity to a human body model or metal surface pattern, a low specific absorption rate SAR (intensity of absorbed radiation) with regard to a human body model when the antenna is placed over or in close proximity to a human body model.

Claims

1. An elastomer composition for embedding a compact antenna, comprising: natural rubber, the elastomer composition is multilayer and the components of the composition whose weights are expressed in parts per hundred parts of rubber by weight of natural rubber consisting essentially of: sulfur1 to 2 phr; phenyl-trichloromethyl-sulfenyl-benzenesulfonamide0.1 to 0.5 phr; diphenylguanidine0.3 to 0.8 phr; tertiary butyl-benzothiazolyl-sulfenamidefrom 1 to 2 phr; dimethylbutyl-phenyl-p-phenylenediamine1.5 phr; polymerized trimethyl dihydro-quinoline1.5 phr; stearic acid2.0 phr; zinc oxide3.0 phr; rapeseed oil15 to 30 phr; bis (triethoxysilylpropyl) tetrasulfide-silanefrom 0.1 to 4.0 phr; 3-thiocyanato-propyl-triethoxy silanefrom 2.0 to 6.0 phr; carbon black5.0 phr; microcrystalline cellulosefrom 20.0 phr to 60.0 phr; and optionally silicon dioxidefrom 10 to 50.0 phr.

2. The elastomer composition intended for embedding a compact antenna according to claim 1, wherein the silicon dioxide is synthetic or rice husks based and is contained in the following amounts: synthetic silicon ranging from 10 to 50 or rice husk based silicon ranging from 10 to 50 or 10-5% or a mixture thereof in a ratio ranging from 1:5 to 5:1.

3. The elastomer composition intended for embedding a compact antenna according to claim 1, wherein the elastomer composition comprises 2 or 3 layers.

4. An elastomer composition for embedding a compact antenna, comprising: natural rubber, the elastomer composition is multilayer and the components of the composition consisting essentially of: sulfur; phenyl-trichloromethyl-sulfenyl-benzenesulfonamide; diphenylguanidine; tertiary butyl-benzothiazolyl-sulfenamide; dimethylbutyl-phenyl-p-phenylenediamine; polymerized trimethyl dihydro-quinoline; stearic acid; zinc oxide; rapeseed oil; bis (triethoxysilylpropyl) tetrasulfide-silane; 3-thiocyanato-propyl-triethoxy silane; carbon black; and microcrystalline cellulose.

Description

DESCRIPTION OF DRAWINGS

[0028] FIG. 1 displays is a reflection coefficient module of the input of an antenna whose metal elements are embedded in a three-layer MCC-2 elastomer composition placed in the free space and on the surface of a three-layer human body model. The presented results are obtained by means of calculation with the finite-difference time domain (FDTD) method.

[0029] FIG. 2 displays the specific absorption rate (SAR) distribution in a three-layer human body model when the antenna is placed on the surface of the skin layer of a three-layer human body model.

[0030] FIG. 3a, FIG. 3b, FIG. 3c, FIG. 3d visualize the antenna configuration.

[0031] FIG. 3a visualizes a front view of the upper radiating element on the first elastomer layer.

[0032] FIG. 3b displays a lower radiating element placed on the second elastomer layer.

[0033] FIG. 3c visualizes a reflector.

[0034] FIG. 3d visualizes the structure of the antenna layers, wherein positions 1, 2, 3, 4, 5 and 6 indicate as follows: 1 constitutes a top radiating element, 2 constitutes the first elastomer layer, 3 constitutes the lower radiating element, 4 constitutes the second elastomer layer, 5 is a reflector and 6 constitutes the third elastomer layer.

PREFERRED EMBODIMENTS OF THE INVENTION

[0035] The present invention is illustrated by the following preferred embodiments represented by different compositions which are never intended to limit the invention scope.

Example 1

[0036] In this example, a specific composition of the elastomer composition is represented which is used in two layers and the amounts of the components are expressed in parts per hundred weights of rubber, and are: sulfur1.6 phr; phenyl-trichloromethyl-sulfenyl-benzenesulfonamide0.3 phr; diphenylguanidine0.5 phr; tertiary butyl-benzothiazolyl-sulfenamide1.5 phr; dimethylbutyl-phenyl-p-phenylenediamine1.5 phr; polymerized trimethyl dihydroquinoline1.5 phr; stearic acid2.0 phr; zinc oxide3.0 phr; rapeseed oil25.0 phr; 3-thiocyanato-propyl-triethoxy silanefrom 2.0 phr to 6.0 phr, carbon black5.0 phr; microcrystalline cellulose60.0 phr; Bis(triethoxysilylpropyl)tetrasulfide (Si 69)0.1 phr natural rubber100 phr.

[0037] The rubber composite is prepared in an open laboratory two rolls mixing mill with roller dimensions L/D 320160 mm, friction 1.7 and slower roller speed 25 min.sup.1. The vulcanization of the rubber composites was carried out on an electrically heated hydraulic press with plates with dimensions 400400 mm at a temperature of 150 C., at 10 MPa and a time determined by the vulcanization isotherms of the composites taken on the MDR 2000 Rheometer manufactured by Alpha Technology.

[0038] The rubber compound is made in the manner described in Table 4.

TABLE-US-00004 TABLE 4 Methods for preparing rubber composite They are : N Elastomers and Ingredients added at: 1. Natural rubber 0 min. 2. Zinc oxide, stearic acid 5 min. 3. Rapeseed oil, compatibles, fillers 10 min. 4. Anti-aging agents - dimethylbutyl-phenyl-p- 20 min. phenylenediamine, polymerized trimethyl dihydroquinoline 5. Accelerators - diphenylguanidine; tertiary butyl- 25 min. benzothiazolyl-sulfenamide 6. sulfur; phenyl-trichloromethylsulfenyl-benzene- 27 min. sulfonamide 7. Removal of the finished rubber compound from the roller 30 min.

Example 2

[0039] The specific values of the elements contained in the elastomer composition which is used for the purposes of the three-layer option are expressed in wt per 100 parts by weight of rubber (phr), namely: sulfur1.6 phr; phenyl-trichloromethyl-sulfenyl-benzenesulfonamide0.3 phr; diphenylguanidine0.5 phr; tertiary butyl-benzothiazolyl-sulfenamide1.5 phr; dimethylbutyl-phenyl-p-phenylenediamine1.5 phr; polymerized trimethyl dihydroquinoline1.5 phr; stearic acid2.0 phr; zinc oxide3.0 phr; rapeseed oil25.0 phr; Bis(triethoxysilylpropyl)tetrasulfide (Si 69)3.0 phr; 3-thiocyanato-propyl-triethoxy silane/Si-264/3.0 phr, carbon black N 5505.0 phr; rice husks based silicon dioxide30.0 phr, microcrystalline cellulose30.0 phr; natural rubber100 phr. The composition has laboratory-grade MCC-2.

[0040] The rubber compound is prepared according to the technology manner and conditions described in Example 1.

Example 3

[0041] The third specific composition related to the elastomer composition is inclusive of the following weight parts, namely: sulfur1.6 phr; phenyl-trichloromethyl-sulfenyl-benzenesulfonamide0.3 phr; diphenylguanidine0.5 phr; tertiary butyl-benzothiazolyl-sulfenamide1.5 phr; dimethylbutyl-phenyl-p-phenylenediamine1.5 phr; polymerized trimethyl dihydroquinoline/anti-aging agent/1.5 phr; stearic acid2.0 phr; zinc oxide3.0 phr; rapeseed oil25.0 phr; Bis(triethoxysilylpropyl)tetrasulfide silane (Si 69)4.0 phr; 3-thiocyanato-propyl-triethoxy silane/Si-264/2.0 phr, carbon black5.0 phr; silicon dioxide/Ultrasil 7000 GR/40.0 phr, microcrystalline cellulose20.0 phr; natural rubber100 phr.

[0042] The rubber compound is prepared according to the technology manner and conditions described in Example 1.

Example 4

[0043] In this example, a specific composition of the elastomer composition is represented and the values of the components are expressed in wt parts per hundred weights of rubber, and are: sulfur1.6 phr; phenyl-trichloromethyl-sulfenyl-benzene-sulfonamide0.3 phr; diphenylguanidine0.5 phr; tertiary butyl-benzothiazolyl-sulfenamide1.5 phr; dimethylbutyl-phenyl-p-phenylenediamine1.5 phr; polymerized trimethyl dihydroquinoline1.5 phr; stearic acid2.0 phr; zinc oxide3.0 phr; rapeseed oil25.0 phr; 3-thiocyanato-propyl-triethoxy silane6.0 phr, carbon black5.0 phr; microcrystalline cellulose60.0 phr; natural rubber100 phr

[0044] Table 5 lists quantitative values of ingredients of exemplary compositions according to the invention at 100 ppmv. natural rubber.

TABLE-US-00005 TABLE 5 Ingredients Example-5 Example-6 1. Natural Rubber/STR-10/ 100 100 2. Microcrystalline cellulose 60 30 3. Rice husks based silicon dioxide 50 15 4. Silicon Dioxide/Ultrasil 7000 GR/ 10 15 5. Carbon black N 550 5 5 6. 3-thiocyanato-propyl-triethoxy silane/Si- 6 3 264/ 7. Bis(triethoxy-silylpropyl)tetrasulfide (Si 69) 0.1 3 8. Rapeseed oil 15 30 9. Zinc oxide 3 3 10. Stearic acid 2 2 11. Polymerized trimethyl dihydro-quinoline/ 1.5 1.5 TMQ/ 12. Dimethylbutyl-phenyl-p-phenylenediamine 1.5 1.5 (6PDD) 13. Tertiary butyl-benzothiazolyl-sulfenamide/ 1 2 TBBS/-accelerator 14. Diphenylguanidine 0.3 0.8 15. Phenyl-trichloromethylsulfenyl-benzene- 0.1 0.5 sulfonamide/Vulkalent E/C/ 16. Sulfur 1 2

[0045] FIG. 3a, FIG. 3b, FIG. 3c, FIG. 3d visualize the configuration of an antenna whose metal elements are embedded in the elastomer composition shown in Example 2.

[0046] The antenna is made up of three componentsa multilayer flexible elastomer pad, a modified version of a planar dipole antenna (emitter) and a rectangular reflector. The elastomer layers are composed of a MCC-2 elastomer composition with a thickness of 1.5 mm and electromagnetic parameters (real part of the permittivity (.sub.r)2.99, imaginary part of the permittivity (.sub.r)0.11, conductivity()0.015). The electromagnetic parameters of the rubber-based synthesis composition are determined by the small interference method at frequency of 2.56 GHz. The reason for using a pad having the composition according to the present invention is due to the fact that it exhibit a good balance of mechanical (high flexibility, ability to withstand mechanical stresses) properties and electromagnetic parameters (low change with regard to .sub.r.sup.,.sub.r.sup.( .sub.) over a wide frequency range. The conductive components of the antenna are made of 0.05 mm thick brass sheet film with regard to the radiating elements and 0.011 mm thick aluminum foil with regard to the reflector. Between layer 2 and layer 3 of the elastomer composition, a reflector is provided, as shown in FIG. 3d to reduce SAR values affecting human tissues when the antenna is placed in close vicinity to the human body.