DE3420195A1 - Process for producing insulating material from scrap paper and/or cardboard - Google Patents

Abstract

The invention relates to a process for producing insulating material, if required in the form of plates, shaped bodies or the like, from scrap paper and/or cardboard, this starting material first being reprocessed to form a fibre mass, then being mixed with additives, foamed and shaped after further processing. It is taken to be novel that plastifiable biopolymers, such as starch, proteins or plastics, are admixed as additives and that the mixture is then compressed and plastified by thermal and mechanical energy input. The mixture can then be expanded by pressure drop and temperature drop on exit from a die.

Description

Process for producing insulating material from waste paper and / or cardboard The invention relates to a method for producing insulating material, possibly in the form of plates, moldings or the like, made of waste paper and / or cardboard, this starting material first worked up to a fiber mass, then mixed with additives, foamed and is shaped after further processing.

Japanese Patent No. 55-149183 discloses a method in which the starting material is fiberized wet by the usual method, the Cutting the paper fibers should be largely avoided. The thus obtained aqueous fiber dispersion, inorganic vesicular materials such as. B. Perlite added. Obtained after dehydration and drying of the mixture thus obtained one made of felted paper fibers and vesicular minerals Masses that can be brought into a desired shape without the use of binders leaves. The mixture is injected into plate-cylinder or other forms and dehydrated and dried therein, sound and heat insulating materials are obtained the desired shape. This material has excellent sound and thermal insulation properties at low weight.

According to an older but not previously published method for Manufacture of material with high sound and thermal insulation properties from waste paper and / or paperboard, the starting material is also first in aqueous fiber form worked up.

The wet fiber mass is then provided with emulsifiers and / or mechanically foamed and structured after preforming with a preservative and shape stabilized. The processed fiber mass can before its stabilization be dried at negative pressure.

Corresponding to an older one, but also not previously published Process for the production of panels, moldings or the like of different gross weights From waste paper and / or cardboard, the raw material is first dry-fiberized, with Binding agents added, shaped, if necessary. compacted and then cured. Here can the raw material is shredded and then dried in a disc refiner fiberized into a wadding-like structure. The addition of binders to the Shredded old fiber material can be used before or during the defibering process take place. Components that cannot be frayed can be used before or during processing be separated. The fibers mixed with the binder are placed on a sieve Scattered to form a fleece, the fibers being watered during the formation of the fleece can be added. This is followed by compaction in a cold press and then drying under hot air. As an alternative, however, it is also possible compressing the nonwoven fabric in a hot press and then curing it.

The invention is based on the method explained at the beginning the underlying task is to reduce insulation material without using conventional binders Density with high sound, insulating and damping properties can be produced cost-effectively.

This object is achieved according to the invention in that as additives plasticizable biopolymers, such as. B. starch, proteins or plastics mixed in be, and that the mixture then by thermal and mechanical energy input is compressed and plasticized. The mixture can then be and pressure drop exiting a nozzle.

If necessary, from the starting material before or during foreign bodies are excreted during further processing.

The starting material can be defibrated wet or dry. It is advantageous according to the invention if the fiber mass before or during Mixing the additives is finely ground. This can e.g. B. by use by refiners or cross beater mills.

The wet or powdery mixture is expediently in the heatable Dosed screw chamber of an extruder, conveyed there by rotation of the screws, compacted and plasticized through the combined introduction of thermal and mechanical energy.

The mixing can take place before or during the thermal and mechanical Energy introduction further recipe components such as B. dyes or oils are added will.

The additives to be mixed with the starting material are used for foaming the mass and possibly also to improve its elasticity. They are film-forming Materials, e.g. B. degraded starches, flour mixes with a high starch content, proteins or plastics such as B. PVC.

The plasticized mass can cause sudden evaporation of the liquid be subjected. This results in an expansion of the mass, which thereby a has a special internal structure.

Through targeted control and pre-forming, various molded parts, Moldings, plates, fillers or the like with low density and high sound, insulating and produce insulation properties. Through further additives and / or subsequent surface treatment can be improved moisture and fire resistance, protection against microorganisms and the like.

In one embodiment, 50% cellulose was used with 50% starch mixed. The mixture, which had a moisture content of 20%, was converted into a heatable Screw chamber of a co-rotating twin screw extruder (Werner and Pfleiderer, Type C 37) metered. The flow temperature was 108 "C; the pressure was about 30 bar set. The specific mechanical energy input was approx. 0.3 Whkg and the product mass flow reached approx. 6 kgh 1 Es under these conditions a foamed strand was formed when the mass emerged from the nozzle.

Claims (7)

Claims: 1. Method for producing insulation material, possibly in the form of plates, moldings or the like, made of waste paper and / or cardboard, this Starting material first worked up into a fiber mass, then with additives is mixed, foamed and shaped after further processing, thereby it is not stated that plasticizable biopolymers as additives, such as B. starch, proteins or plastics are mixed in, and that the mixture then compacted and plasticized by introducing thermal and mechanical energy will. 2. The method according to claim 1, characterized in that the fiber mass before or during the addition of the additives @@@@ v @@ grinding. 3. The method according to claim 1 or 2, characterized in that the Mixing before the introduction of thermal energy occurs. "K1 itrl w 1 4. Procedure according to claim 1, 2 or 3, characterized in that the plasticized mass is subjected to sudden liquid evaporation. 5. The method according to any one of the preceding claims, characterized in, that in the mixture before or during the thermal and mechanical energy introduction other recipe components such as B. dyes or oils are added. 6. The method according to any one of the preceding claims, characterized in, that flour mixtures with a high proportion of starch are used as additives. 7. The method according to any one of the preceding claims, characterized through the use of a heatable screw extruder for the thermal and mechanical energy input for plasticizing the mixture.