ES2345087B1 - THERMOCOMPRESSABLE FELT. - Google Patents

Abstract

Thermal compressible felt.

Felt comprising a polymer or copolymer expandable from 10% to 30% by weight than in its condensation or fusion releases gas for the formation of microcells, a binder or thermosetting binder from 20% to 45% by weight, the rest up to complete 100% recycled fibers. Felt it presents a surface barrier in an alternative embodiment antihumidity or addition of flame retardant agent.

Description

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Thermal compressible felt.

Object of the invention

The present invention relates to a felt thermocompressible, for use in decorative and other panels, liable to apply in various fields such as construction, The car and others.

Background of the invention

At present, the use of materials thermocompressible, in many cases fire retardant, extends mostly in the manufacture of cars, trains, ships, etc; and also under construction.

Textile-based felt consists of fibers of cotton, vegetable, artificial or synthetic fibers; recycled or not, in various proportions.

Among the fibers used for manufacturing of felt, together with cotton as the main component, highlights the fibers of plant origin, such as hemp, flax or Jute, among others. Fibers are also commonly used artificial such as rayon, viscose, and others, and synthetic fibers such as all polymers for commercial use indistinctly.

The above mentioned components are add a binder or binder, to provide consistency and minimum stiffness. These binders are synthetic resins thermosetting agents or mixtures thereof, may also be occasionally modified thermoplastic resins or low polymer fibers melting point.

Industrially, the felt can be found in Two states, depending on the progress in the production process:

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State prepolymerized, in which the binder has not yet fully condensed, and therefore can be used for production of thermoformed parts.

Polymerized state, in which the binder It is almost completely condensed, forming networks three-dimensional, which provide mechanical properties to the material.

To condense or polymerize the monomer structural of the binder is necessary to provide heat and pressure raised inside a metal mold.

The temperature and pressure parameters depend of the normative objectives, and the type of material used. One time which has completely polymerized the felt, it has more consistency and stiffness provided by the binding of the binder with the fibers

In short, the final properties of felt will depend on the material used, in terms of fibers, of the binder or binder, also of its percentages, and even of the parameters of temperature, pressure, as well as the mold geometry.

That is why varying the binder and its polymerization process, different products can be obtained finishes, that is, felt of various densities or pieces of different geometries with their characteristic properties mechanical

Felts are applicable to a wide variety from industries, especially to the automobile industry and also to the construction All these materials must present certain impact resistance, acoustic and thermal properties, flexural and other resistance. They must also meet requirements of combustion resistance. Currently, in the industry, mainly the automotive industry, a great variety of panels is known interiors, whose decorative function entails or demands some functions of security, welfare and others.

A large part of the pieces, such as interior roof coverings or door panels, have to meet its flexural and absorption resistance regulations acoustics.

To understand the resistance requirements to bending it is necessary to see how and why they are performed. Let's take as example a roof covering of a conventional car.

Currently the materials used are of polyurethane foam to which fibers of high tenacity glass, coming from "rowings" that They cut to the required length. Special nonwovens are added with various finishes (water repellent, flame retardant, others). These nonwovens are they call skin, and one of its functions is to retain the fibers of glass and facilitate subsequent thermoforming.

The economic cost of this process is high, both for the cost of the foam and for the glass fibers, such as also for the nonwovens that make skin. Leaving aside the processes for decorative finishing that are not of interest.

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The main requirements of a roof lining are:

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Good flexural strength in different humidity conditions and temperature.

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Good sound absorption

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Self-supporting: That is, adapt to the body shape and preserve it over time,

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Thermal isolation.

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Dimensional stability high.

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Low or zero emissions.

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Combustion resistance

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Recyclability of the material.

The current solution presents the following inconveniences:

to)

dimensional stability improvable,

b)

the sound absorption is improvable,

C)

he thermal insulation is improvable,

d)

emissions, although minimal, of glass microfibers, this means toxicity,

and)

It is not satisfactorily recyclable.

Flexural strength is physically evaluable with Young's module. Experience teaches that thermocompressed materials, of equal thickness and with equal weight (weight per unit area), the ones that resist the most flexion are those that have greater capacity to absorb or dissipate the energy in the form of pressure to which it is subjected. This is so compared to high thermal insulation materials, whose properties need high viscoelasticity.

Hence, the importance of viscoelasticity of the material and its ability to absorb mechanical energy, be it in the form of acoustic, mechanical or vibration pressure produced by heat.

The sound absorption depends on the resonance, In other words, the viscoelastic property of materials comprising the coating. In short, of the ability to absorb deformations, but in this case also, It also depends on the resistance to the passage of air. The materials that have great sound absorption capacity are materials that They have a lot of pore, which also has a large area. This loss of load when the air passes is the one that reduces the pressure sound

Thermal insulation and stability dimensional, they have a lot to do with the above, and also with the chemical structure of the components. The presence of links multiple in the unions and their ability to relocate are Extremely important conditions to absorb heat.

Description of the invention

The thermocompressible felt, object of the proposed invention, comprises a felt that has some Improved mechanical properties of rigidity and self-support, with the advantage of not emitting harmful gases because of its composition, and that in addition it presents a zero emission of microparticles or toxic fibers, being susceptible to being flame retardant.

According to the invention, the felt further comprises of plant, artificial, synthetic, or polymeric fibers of low melting point; an expandable polymer or copolymer, mainly by the release of gas in its condensation or fusion, and a thermosetting binder or binder.

The aforementioned reaction that occurs in the thermocompression of the felt can come from oxidation or sublimation of any of the following polymers:

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ABS or ABS / SAN in pellet with micropore treatment, susceptible to expand.

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PP (polypropylene) with micropore treatment, susceptible to expand,

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$ (polystyrene) with micropore treatment, susceptible to expand.

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PP (polypropylene) or PS (polystyrene) and / or ABS / SAN already expanded Recycled into small particles. These materials come in your entire recovery of packaging, containers for food, defective or unused construction materials, even interior recoveries of bumpers or panels car doors, etc.

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Any other type of polymer or copolymer whose condemnation or fusion or sublimation releases gas (in its mostly CO 2).

Polymers that have been treated for expand, they contain in many cases functional groups, which by sublimating they release CO2 (carbon dioxide), this gas is trapped in small cells, giving the vegetable felt with binder or thermosetting binder an additional stiffness, but at the same time elasticity since these are tiny cells distributed throughout the volume that are likely to absorb the energy to deform. In addition, the level of stiffness is achieved, with significantly lower part weight.

Vegetable fibers, especially fibers Cotton behave due to its microtube configuration with great sonic and thermal absorption as we have seen before.

According to its composition, this felt does not presents harmful emissions, as opposed to felts vegetables with phenolic type binders or foam pieces previously mentioned. The fact of no should be emphasized emission of solid particles as opposed to the emission of felt microfibers containing fiberglass or rock wool

The thermosetting binder presents the advantage of chemical non-reversibility as opposed to thermoplastic binder felts. This feature is very important for, for example, low dimensional stability various climates

It is also planned that the piece produced with felt have moisture barriers to add in the same process felt production, or later in the thermoforming. Said barriers may be aluminum or non-woven sheets of polyester, or polyamide polyester, or viscose polyester, or oxidized polyacrylonitrile.

It is worth highlighting the recyclability of the material, since that all its composition is totally and easily recyclable.

Preferred Embodiment of the Invention

In preferred embodiment of the felt Thermocompressible comprises the following components:

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expandable polymer or copolymer 10 - 30% by weight.

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Thermosetting binder or binder: 20 - 45% by weight.

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Fibers (vegetable, artificial or synthetic / optionally mixed with thermoplastics): to complete 100%.

In an alternative embodiment, the felt it comprises a surface barrier configured by a sheet of aluminum or nonwovens.

In an alternative embodiment there is the possibility of adding flame retardant agent.

Once nature is sufficiently described of the invention, as well as a preferred embodiment, for the appropriate purposes that the materials, form, size and arrangement of the elements described may be modified, as long as this does not imply an alteration of the essential features of the invention claimed in continuation.

Claims (5)

1. Thermocompressible felt, of the type comprising plant fibers, and comprising an expandable polymer or copolymer that releases gas, and a thermosetting binder or binder, characterized in that it comprises 10% expandable polymer or copolymer. at 30% by weight, thermosetting binder or binder from 20% to 45% by weight, and vegetable fibers or mixed with synthetic or artificial fibers until 100% is completed. 2. Felt according to the preceding claim, characterized in that the vegetable fibers are mixed with thermoplastic fibers. 3. Felt, according to any of the preceding claims, characterized in that the expandable polymer or copolymer facilitates the creation of inner gas microcells. 4. Felt, according to any of the preceding claims, characterized in that it comprises a moisture barrier constituted by at least one nonwoven sheet of polyester, polyester-polyamide, or viscose polyester or oxidized polyacrylonitrile. 5. Felt, according to any of the preceding claims, characterized in that it includes a flame retardant agent.