阅读说明：本技术 一种抗开裂光电复合缆材料 (Anti-cracking photoelectric composite cable material ) 是由 李超 郭在红 刘玲 詹懿 于 2020-12-08 设计创作，主要内容包括：一种抗开裂光电复合缆材料,由以下重量份的原料制成：氯丁橡胶12-18份,聚乙烯20-30份,三元乙丙橡胶8-10份,乙烯-丙烯酸甲酯共聚物15-25份,聚丙烯纤维5-10份,纳米二氧化钛5-10份,阻燃剂8-16份,填充剂6-15份,防老剂4-10份,软化剂2-5份,交联剂2-6份和助交联剂0.5-2份,γ-氨丙基三乙氧基硅烷0.5-3份、过氧化二异丙苯1.5-2份、硬脂酸0.5-1.0份、三钼酸铵0.1-1.5份、辣椒素0.5-2.0份、硫黄0.1-1.5份,具有较高的热稳定性、抗老化性。更好的耐腐蚀性、耐油性、耐泥浆性,具有稳定的耐温性,具有较好的抗开裂性。(An anti-cracking photoelectric composite cable material is prepared from the following raw materials in parts by weight: 12-18 parts of chloroprene rubber, 20-30 parts of polyethylene, 8-10 parts of ethylene propylene diene monomer, 15-25 parts of ethylene-methyl acrylate copolymer, 5-10 parts of polypropylene fiber, 5-10 parts of nano titanium dioxide, 8-16 parts of flame retardant, 6-15 parts of filler, 4-10 parts of anti-aging agent, 2-5 parts of softener, 2-6 parts of crosslinking agent and 0.5-2 parts of auxiliary crosslinking agent, 0.5-3 parts of gamma-aminopropyltriethoxysilane, 1.5-2 parts of dicumyl peroxide, 0.5-1.0 part of stearic acid, 0.1-1.5 parts of ammonium trimolybdate, 0.5-2.0 parts of capsaicin and 0.1-1.5 parts of sulfur, and has high thermal stability and ageing resistance. Better corrosion resistance, oil resistance, mud resistance, stable temperature resistance and better cracking resistance.)

1. An anti-cracking photoelectric composite cable material is prepared from the following raw materials in parts by weight: 12-18 parts of chloroprene rubber, 20-30 parts of polyethylene, 8-10 parts of ethylene propylene diene monomer, 15-25 parts of ethylene-methyl acrylate copolymer, 5-10 parts of polypropylene fiber, 5-10 parts of nano titanium dioxide, 8-16 parts of flame retardant, 6-15 parts of filler, 4-10 parts of anti-aging agent, 2-5 parts of softener, 2-6 parts of crosslinking agent and 0.5-2 parts of auxiliary crosslinking agent, 0.5-3 parts of gamma-aminopropyltriethoxysilane, 1.5-2 parts of dicumyl peroxide, 0.5-1.0 part of stearic acid, 0.1-1.5 parts of ammonium trimolybdate, 0.5-2.0 parts of capsaicin and 0.1-1.5 parts of sulfur.

2. The crack-resistant optical-electrical composite cable material of claim 1, wherein: the chloroprene rubber: ethylene propylene diene monomer: nitrile rubber: chlorinated polyethylene: polyethylene wax melting: chlorinated paraffin ═ 14: 7: 4: 15: 1: 2.

3. the crack-resistant optical-electrical composite cable material of claim 1, wherein: the flame retardant is one or more of antimony trioxide, magnesium hydroxide, aluminum oxide, zinc oxide and zinc borate.

4. The crack-resistant optical-electrical composite cable material of claim 1, wherein: the filler is one or more of light calcium carbonate, carbon black N330, carbon black N550 and carbon black N660.

5. The crack-resistant optical-electrical composite cable material of claim 1, wherein: the softener is dimethyl silicone oil or hydroxyl silicone oil.

6. The crack-resistant optical-electrical composite cable material of claim 1, wherein: the anti-aging agent is one or more of OD, MB and 4010 NA.

7. The crack-resistant optical-electrical composite cable material of claim 1, wherein: the cross-linking agent is one or more of dicumyl peroxide, benzoyl peroxide, 2, 5-dimethyl-2, 5-di (tert-butyl peroxy) hexane, 1, 3-bis (2-tert-butyl peroxy isopropyl) benzene and 1, 4-bis (tert-butyl peroxy isopropyl) benzene.

8. The crack-resistant optical-electrical composite cable material of claim 1, wherein: the auxiliary crosslinking agent is one or more of N, N' -m-phenylene bismaleimide, triallyl isocyanurate and ethylene dimethacrylate.

9. A method of making a crack resistant optical-electrical composite cable material according to any one of claims 1-8, comprising: 12-18 parts of chloroprene rubber, 20-30 parts of polyethylene, 8-10 parts of ethylene propylene diene monomer, 15-25 parts of ethylene-methyl acrylate copolymer, 5-10 parts of polypropylene fiber, 5-10 parts of nano titanium dioxide, 8-16 parts of flame retardant, 6-15 parts of filler, 4-10 parts of anti-aging agent, 2-5 parts of softener, 2-6 parts of crosslinking agent and 0.5-2 parts of auxiliary crosslinking agent, 0.5-3 parts of gamma-aminopropyltriethoxysilane, 0.5-1.0 part of stearic acid and 0.1-1.5 parts of ammonium trimolybdate, 0.5-2.0 parts of capsaicin and 0.1-1.5 parts of sulfur are uniformly mixed in an internal mixer, when the temperature reaches a proper condition, a pressure cover is lifted, air is exhausted for 30s, the internal mixing is continued until the complete plasticization of the materials is finished, and the materials are extruded and granulated in an extruder.

Technical Field

The invention relates to the technical field of simultaneous transmission of communication optical cables and power cables, in particular to an anti-cracking photoelectric composite cable.

Background

The photoelectric composite cable integrates optical fiber and a transmission copper wire into a whole, is suitable for a broadband access network system, and can solve the problems of broadband access, equipment power consumption and signal transmission.

With the rapid development of industry, photoelectric composite cables have been widely used in the fields of petroleum, chemical engineering, ocean engineering, rail transit, urban local area networks, commercial internet of things, digital communication and the like in China, and the requirements of the fields on the quality and performance of the photoelectric composite cables are improved, particularly the cracking resistance of the photoelectric composite cables and accidents caused by poor cracking resistance of the photoelectric composite cables are on the rise every year. Similarly, the MPO pretermination optical cable is suitable for high-density application of a data center, provides optical fiber connection from 12 cores to 144 cores, can effectively prevent the optical cable and the optical fiber connector from being damaged in the transportation and installation process by designing the formula of the sheath material of the photoelectric composite cable or the MPO optical cable, and resists the tensile resistance of 450N which is possibly met by the trunk optical cable of the pretermination optical cable in a wire slot.

Chinese patent application with publication number CN108410045A discloses a high-temperature-resistant flame-retardant nontoxic cable material. The cable material comprises the following components: polyolefin thermoplastic elastomer, polyurethane elastomer rubber, ethylene propylene diene monomer rubber, ceramic powder, trioctyl trimellitate, zinc stearate, reinforcing agent, nano silicon dioxide, silane coupling agent, flame retardant, smoke suppressant and antioxidant. Wherein the ceramic powder is prepared from attapulgite clay, montmorillonite, sepiolite and other materials by modifying, calcining and grinding. The polyurethane elastomer rubber is polycaprolactone type thermoplastic polyurethane elastomer rubber, and the reinforcing agent is high wear-resistant carbon black; the flame retardant is a mixture of nano aluminum dioxide, nano magnesium dioxide and antimony oxide, and the mass ratio of the nano aluminum dioxide to the nano magnesium dioxide to the antimony oxide is 2:4: 3; the smoke suppressant is one of zinc borate, molybdenum trioxide and organically modified montmorillonite. The cable material has outstanding high-temperature resistance, good flame retardant property and very green and safe performance. However, the polyolefin thermoplastic elastomer in the patent is used in a large amount, and the strength of the cable material is influenced.

The Chinese patent application with the publication number of 108485124A discloses a flame-retardant high-toughness halogen-free environment-friendly cable material and a preparation method thereof, which relate to the field of cable materials and comprise the following raw materials in parts by weight: 30-40 parts of PVC resin, 15-25 parts of phenolic resin, 8-16 parts of maleic anhydride grafted polypropylene, 6-12 parts of diatomite, 5-10 parts of mica powder, 3-6 parts of saponite powder, 6-12 parts of polypropylene fiber, 4-7 parts of silicon carbide, 2-4 parts of carbon black, 3-5 parts of chitin, 4-6 parts of nano titanium dioxide, 3-5 parts of antimony trioxide, 0.8-1.5 parts of coupling agent, 1.2-2.5 parts of flame retardant and 1.5-2.8 parts of antioxidant; the cable material has good flame retardance and toughness, excellent tensile resistance and breaking resistance, no halogen substance, environmental protection, simple preparation method and easy production. However, the cable material disclosed by the patent adopts a large amount of PVC resin, and the obtained cable material is low in impact strength and poor in oil resistance.

The photoelectric composite cable has certain defects in the design of a formula and the selection of materials, and is not well solved all the time.

Disclosure of Invention

The invention aims to provide an anti-cracking photoelectric composite cable aiming at the defects in the prior art.

In order to achieve the purpose, the invention adopts the technical scheme that: an anti-cracking photoelectric composite cable material is prepared from the following raw materials in parts by weight:

12-18 parts of chloroprene rubber, 20-30 parts of polyethylene, 8-10 parts of ethylene propylene diene monomer, 15-25 parts of ethylene-methyl acrylate copolymer, 5-10 parts of polypropylene fiber, 5-10 parts of nano titanium dioxide, 8-16 parts of flame retardant, 6-15 parts of filler, 4-10 parts of anti-aging agent, 2-5 parts of softener, 2-6 parts of crosslinking agent and 0.5-2 parts of auxiliary crosslinking agent, 0.5-3 parts of gamma-aminopropyltriethoxysilane, 1.5-2 parts of dicumyl peroxide, 0.5-1.0 part of stearic acid, 0.1-1.5 parts of ammonium trimolybdate, 0.5-2.0 parts of capsaicin and 0.1-1.5 parts of sulfur.

Preferably, the weight ratio of the chloroprene rubber: ethylene propylene diene monomer: nitrile rubber: chlorinated polyethylene: polyethylene wax melting: chlorinated paraffin ═ 14: 7: 4: 15: 1: 2. the proportion is the optimal proportion of the chloroprene rubber, the ethylene propylene diene monomer rubber, the nitrile rubber, the chlorinated polyethylene, the chemical polyethylene wax and the chlorinated paraffin, so that the anti-cracking performance is good.

Preferably, the flame retardant is one or more of antimony trioxide, magnesium hydroxide, aluminum oxide, zinc oxide and zinc borate.

Preferably, the filler is one or more of light calcium carbonate, carbon black N330, carbon black N550 and carbon black N660.

Preferably, the anti-aging agent is one or more of OD, MB and 4010 NA.

Preferably, the softener is dimethyl silicone oil or hydroxyl silicone oil.

Preferably, the crosslinking agent is one or more of dicumyl peroxide, benzoyl peroxide, 2, 5-dimethyl-2, 5-di (tert-butylperoxy) hexane, 1, 3-bis (2-tert-butylperoxyisopropyl) benzene and 1, 4-bis (tert-butylperoxyisopropyl) benzene.

Preferably, the auxiliary crosslinking agent is one or more of N, N' -m-phenylene bismaleimide, triallyl isocyanurate and vinyl dimethacrylate.

The preparation method of the anti-cracking photoelectric composite cable material comprises the following steps:

12-18 parts of chloroprene rubber, 20-30 parts of polyethylene, 8-10 parts of ethylene propylene diene monomer, 15-25 parts of ethylene-methyl acrylate copolymer, 5-10 parts of polypropylene fiber, 5-10 parts of nano titanium dioxide, 8-16 parts of flame retardant, 6-15 parts of filler, 4-10 parts of anti-aging agent, 2-5 parts of softener, 2-6 parts of crosslinking agent and 0.5-2 parts of auxiliary crosslinking agent, 0.5-3 parts of gamma-aminopropyltriethoxysilane, 0.5-1.0 part of stearic acid and 0.1-1.5 parts of ammonium trimolybdate, 0.5-2.0 parts of capsaicin and 0.1-1.5 parts of sulfur are uniformly mixed in an internal mixer, when the temperature reaches a proper condition, a pressure cover is lifted, air is exhausted for 30s, the internal mixing is continued until the complete plasticization of the materials is finished, and the materials are extruded and granulated in an extruder.

The invention has the beneficial effects that:

1. the chloroprene rubber has the advantages of excellent oil resistance, higher wear resistance, better heat resistance and strong bonding force; the polyethylene has higher softening temperature and melting temperature, has the advantages of high strength, good toughness, high rigidity, heat resistance and cold resistance, also has good environmental stress crack resistance, impact resistance and tearing resistance, and can resist acid, alkali and organic solvents; the ethylene-methyl acrylate copolymer has high stability, excellent stress fracture resistance and low-temperature impact strength; the chloroprene rubber, the polyethylene and the ethylene-methyl acrylate copolymer are used as the base material of the cable material, and the obtained cable material has the advantages of cracking resistance, high toughness and excellent high temperature resistance. The polypropylene fiber has the advantages of light weight, high strength, good elasticity, wear resistance, corrosion resistance, heat resistance and aging resistance, is easy to form an interpenetrating network structure with the base material, and further enhances the strength and flexibility of the base material; the nano titanium dioxide is dispersed in the base material network structure, so that the wear resistance and flexibility of the cable material are improved. The raw materials are used together, the tensile strength of the obtained high-toughness anti-cracking cable material is more than or equal to 22MPa, the tear strength is more than or equal to 8.5N/mm, the tensile elongation is more than or equal to 453 percent, and the cable material is good in toughness and anti-cracking; after hot air aging treatment, the tensile elongation retention rate is more than or equal to 90.5%, after IBM903 standard oil treatment, the tensile elongation retention rate is more than or equal to 92.1%, and the cable material has excellent high-temperature resistance, oil resistance and aging resistance.

2. The flame retardant is one or more of antimony trioxide, magnesium hydroxide, aluminum oxide, zinc oxide and zinc borate, and has the advantages of good flame retardant performance, low smoke, low toxicity, environmental friendliness. The filler is one or more of light calcium carbonate, carbon black N330, carbon black N550 and carbon black N660, and the strength of the cable material is improved. The anti-aging agent is one or more of OD, MB and 4010NA, so that the oxidation process of the cable material is prevented and slowed down, and the service life of the cable material is prolonged. The softener is dimethyl silicone oil or hydroxyl silicone oil, so that the fluidity of the raw materials is improved, the mixing time is shortened, and the rapid and uniform dispersion of various raw materials is promoted. The cross-linking agent is one or more of dicumyl peroxide, benzoyl peroxide, 2, 5-dimethyl-2, 5-di (tert-butyl peroxy) hexane, 1, 3-bis (2-tert-butyl peroxy isopropyl) benzene and 1, 4-di-tert-butyl peroxy isopropyl benzene, so that the cable material can form a three-dimensional network structure more easily, and the mechanical property of the cable material is improved. The auxiliary crosslinking agent is one or more of N, N' -m-phenylene bismaleimide, triallyl isocyanate and ethylene dimethacrylate, and is favorable for shortening the crosslinking time.

3. The high-toughness anti-cracking cable material has the advantages of few raw material types, simple preparation method, good cross-linking effect of each raw material and low cost.

4. Stearic acid, ammonium trimolybdate, capsaicin and sulfur form a three-dimensional network structure with better toughness and crack resistance.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The invention is further described with reference to the following examples.

Example 1

An anti-cracking photoelectric composite cable material is prepared from the following raw materials in parts by weight:

12 parts of chloroprene rubber, 20 parts of polyethylene, 8 parts of ethylene propylene diene monomer, 15 parts of ethylene-methyl acrylate copolymer, 5 parts of polypropylene fiber, 5 parts of nano titanium dioxide, 8 parts of flame retardant, 6 parts of filler, 4 parts of anti-aging agent, 2 parts of softener, 2 parts of crosslinking agent and auxiliary crosslinking agent, 3 parts of gamma-aminopropyl triethoxysilane, 2 parts of dicumyl peroxide, 1.0 part of stearic acid, 1.5 parts of ammonium trimolybdate, 2.0 parts of capsaicin and 1.5 parts of sulfur.

The flame retardant is antimony trioxide.

The filler is light calcium carbonate.

The anti-aging agent is OD.

The softener is dimethyl silicone oil.

The cross-linking agent is dicumyl peroxide.

The auxiliary crosslinking agent is N, N' -m-phenylene bismaleimide.

The preparation method of the photoelectric composite cable material comprises the following steps:

18 parts of chloroprene rubber, 30 parts of polyethylene, 8 parts of ethylene propylene diene monomer, 15 parts of ethylene-methyl acrylate copolymer, 5 parts of polypropylene fiber, 5 parts of nano titanium dioxide, 8 parts of flame retardant, 6 parts of filler, 4 parts of anti-aging agent, 2 parts of softener, 2 parts of crosslinking agent, 2 parts of auxiliary crosslinking agent, 3 parts of gamma-aminopropyltriethoxysilane, 2 parts of dicumyl peroxide, 1.0 part of stearic acid, 1.5 parts of ammonium trimolybdate, 2.0 parts of capsaicin and 1.5 parts of sulfur are uniformly mixed in an internal mixer, when the temperature reaches a proper condition, the internal mixer is lifted and pressed, air is exhausted for 30s, the internal mixing is continued until the complete plasticization of the materials, and the materials are extruded and granulated in an extruder.

Example 2

The photoelectric composite cable material is prepared from the following raw materials in parts by weight:

an anti-cracking photoelectric composite cable material is prepared from the following raw materials in parts by weight:

12 parts of chloroprene rubber, 20 parts of polyethylene, 8 parts of ethylene propylene diene monomer, 15 parts of ethylene-methyl acrylate copolymer, 5 parts of polypropylene fiber, 5 parts of nano titanium dioxide, 8 parts of flame retardant, 6 parts of filler, 4 parts of anti-aging agent, 2 parts of softener, 2 parts of crosslinking agent and auxiliary crosslinking agent, 3 parts of gamma-aminopropyl triethoxysilane, 2 parts of dicumyl peroxide, 1.0 part of stearic acid, 1.5 parts of ammonium trimolybdate, 2.0 parts of capsaicin and 1.5 parts of sulfur.

The flame retardant is antimony trioxide.

The filler is light calcium carbonate.

The anti-aging agent is OD.

The softener is dimethyl silicone oil.

The cross-linking agent is dicumyl peroxide.

The auxiliary crosslinking agent is N, N' -m-phenylene bismaleimide.

The preparation method of the photoelectric composite cable material comprises the following steps:

12 parts of chloroprene rubber, 20 parts of polyethylene, 8 parts of ethylene propylene diene monomer, 15 parts of ethylene-methyl acrylate copolymer, 5 parts of polypropylene fiber, 5 parts of nano titanium dioxide, 8 parts of flame retardant, 6 parts of filler, 4 parts of anti-aging agent, 2 parts of softener, 2 parts of crosslinking agent, 2 parts of auxiliary crosslinking agent, 3 parts of gamma-aminopropyltriethoxysilane, 2 parts of dicumyl peroxide, 1.0 part of stearic acid, 1.5 parts of ammonium trimolybdate, 2.0 parts of capsaicin and 1.5 parts of sulfur are uniformly mixed in an internal mixer, when the temperature reaches a proper condition, the internal mixer is lifted and pressed, air is exhausted for 30s, the internal mixing is continued until the complete plasticization of the materials, and the materials are extruded and granulated in an extruder.

Example 3

An anti-cracking photoelectric composite cable material is prepared from the following raw materials in parts by weight: 15 parts of chloroprene rubber, 26 parts of polyethylene, 10 parts of ethylene propylene diene monomer, 25 parts of ethylene-methyl acrylate copolymer, 10 parts of polypropylene fiber, 10 parts of nano titanium dioxide, 16 parts of flame retardant, 15 parts of filler, 10 parts of anti-aging agent, 5 parts of softener, 6 parts of crosslinking agent and 2 parts of auxiliary crosslinking agent, 3 parts of gamma-aminopropyl triethoxysilane, 2 parts of dicumyl peroxide, 1.0 part of stearic acid, 1.5 parts of ammonium trimolybdate, 2.0 parts of capsaicin and 1.5 parts of sulfur.

The flame retardant is zinc borate.

The filler is carbon black N660.

The anti-aging agent is 4010 NA.

The softener is hydroxy silicone oil.

The cross-linking agent is per-2, 5-dimethyl-2, 5-di (tert-butylperoxy) hexane.

The auxiliary crosslinking agent is N, N' -m-phenylene bismaleimide.

The preparation method of the photoelectric composite cable material comprises the following steps:

18 parts of chloroprene rubber, 30 parts of polyethylene, 10 parts of ethylene propylene diene monomer, 25 parts of ethylene-methyl acrylate copolymer, 10 parts of polypropylene fiber, 10 parts of nano titanium dioxide, 16 parts of flame retardant, 15 parts of filler, 10 parts of anti-aging agent, 5 parts of softener, 6 parts of crosslinking agent, 2 parts of auxiliary crosslinking agent, 3 parts of gamma-aminopropyltriethoxysilane, 2 parts of dicumyl peroxide, 1.0 part of stearic acid, 1.5 parts of ammonium trimolybdate, 2.0 parts of capsaicin and 1.5 parts of sulfur are uniformly mixed in an internal mixer, when the temperature reaches a proper condition, the internal mixer is lifted and pressed, air is exhausted for 30s, the internal mixing is continued until the complete plasticization of the materials, and the materials are extruded and granulated in an extruder.

Comparative example 1:

an anti-cracking photoelectric composite cable material is prepared from the following raw materials in parts by weight: 15 parts of styrene butadiene rubber, 26 parts of polyvinyl chloride, 10 parts of ethylene propylene diene monomer, 25 parts of ethylene-methyl acrylate copolymer, 10 parts of polypropylene fiber, 10 parts of nano titanium dioxide, 16 parts of flame retardant, 15 parts of filler, 10 parts of anti-aging agent, 5 parts of softener, 6 parts of crosslinking agent and 2 parts of auxiliary crosslinking agent, 3 parts of gamma-aminopropyl triethoxysilane, 2 parts of dicumyl peroxide, 1.0 part of stearic acid, 1.5 parts of ammonium trimolybdate, 2.0 parts of capsaicin and 1.5 parts of sulfur.

The flame retardant is zinc borate.

The filler is carbon black N660.

The anti-aging agent is 4010 NA.

The softener is hydroxy silicone oil.

The cross-linking agent is per-2, 5-dimethyl-2, 5-di (tert-butylperoxy) hexane.

The auxiliary crosslinking agent is N, N' -m-phenylene bismaleimide.

The preparation method of the photoelectric composite cable material comprises the following steps:

the preparation method comprises the following steps of uniformly mixing 15 parts of styrene butadiene rubber, 26 parts of polyvinyl chloride, 10 parts of ethylene propylene diene monomer, 25 parts of ethylene-methyl acrylate copolymer, 10 parts of polypropylene fiber, 10 parts of nano titanium dioxide, 16 parts of flame retardant, 15 parts of filler, 10 parts of anti-aging agent, 5 parts of softener, 6 parts of crosslinking agent, 2 parts of auxiliary crosslinking agent, 3 parts of gamma-aminopropyltriethoxysilane, 2 parts of dicumyl peroxide, 1.0 part of stearic acid, 1.5 parts of ammonium trimolybdate, 2.0 parts of capsaicin and 1.5 parts of sulfur in an internal mixer, lifting a pressurizing cover when the temperature reaches a proper condition, exhausting for 30s, continuously carrying out internal mixing until the materials are completely plasticized, and carrying out extrusion granulation in an extruder.

Detection group	Experimental example 1	Experimental example 2	Experimental example 3	Comparative example 1
					Bending strength	256	220	236	130
Tensile strength	180Mpa	158Mpa	168Mpa	120Mpa
					Elongation at break	388％	326％	308％	200％
Density (kg/m)3)	1024	998	968	785

Unless otherwise specified, various starting materials of the present invention are commercially available; or prepared according to conventional methods in the art. Unless defined or stated otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In addition, any methods and materials similar or equivalent to those described herein can be used in the methods of the present invention.

Other aspects of the invention will be apparent to those skilled in the art in view of the disclosure herein.

The foregoing description of the specific embodiments, while further illustrating the invention, should be understood. These examples are intended to illustrate the invention and are not intended to limit the scope of the invention. The experimental methods of the following examples, which are not specified under specific conditions, are generally determined according to national standards. If there is no corresponding national standard, it is carried out according to the usual international standards, to the conventional conditions or to the conditions recommended by the manufacturer. Unless otherwise indicated, all parts are parts by weight and all percentages are percentages by weight.