WO2002010283A1

WO2002010283A1 - Natural resin based thermoplastic material

Info

Publication number: WO2002010283A1
Application number: PCT/EP2001/008826
Authority: WO
Inventors: Norbert Mundigler; Markus Eibl
Original assignee: Norbert Mundigler; Markus Eibl
Priority date: 2000-08-01
Filing date: 2001-07-31
Publication date: 2002-02-07
Also published as: DE10193049D2; AU2001291706A1; AT410212B; ATA13402000A

Abstract

The invention relates to a highly deformable bio-degradable thermoplastic material, containing a protein and a chemically modified natural resin. Moulded bodies can be produced for various applications by said recyclable thermoplastic material, particularly by means of injection moulding.

Description

THERMOPLASTIC MEASUREMENT BASED ON NATURAL RESIN

TECHNICAL AREA

The invention relates to a thermoplastic composition containing a resin and a protein, a process for their preparation and moldings obtainable therefrom.

BACKGROUND AND GENERAL PRIOR ART

A large number of synthetic materials, some of which contain natural substances, are known for a wide variety of purposes, in particular for accessories, furniture elements of all kinds, and for a wide variety of industries and commercial areas, but they have the disadvantage that they are not environmentally friendly to dispose of and at least to a significant extent are not biodegradable.

Recently, efforts have been made to provide materials that consist entirely or at least for the most part of natural materials and that have the same good formability and comparable properties as the known materials. Another criterion in the development of such substances is the processability of these new moldable substances using conventional processes and in existing plants.

A thermoplastic material mass of the type mentioned is known from EP-B - 0 675 920 and FR-B - 837.617.

According to EP-B-0 675 920, the composition that can be used as a material for injection molding contains at least one natural resin and one or more natural products containing starches and / or protein. Copals, damar resins and gilsonite are used as natural resins. The composition according to FR-B - 837.617 comprises a substance selected from the group of proteins, starches and their derivatives and colloidally soluble in water, a resinous material such as a natural or synthetic resin, a solvent for the resinous material, an alkali and a organic aluminum salt.

Natural resins are to be understood here as resins of plant or animal origin, whereby plant-based natural resins are based on excretions (exudates) from special plants, mostly trees, which flow out as sticky masses after natural or artificial injuries and are more volatile in the air due to evaporation Solidify components as well as polymerization and oxidation reactions. Fossil natural resins such as Copals, Kaurikopale or amber are found worldwide as deposits. Freshly obtained natural resins are known, for example, under the names acaroid resins, Canada balm, Japanese lacquer, damar resin, dragon blood, myrrh, Venetian turpentine, rosin etc.

Natural resins mainly contain resin acids and have a certain surface stickiness.

The unfavorable properties of the natural resins include low temperature and aging resistance, in particular low resistance to oxygen, which leads to unsightly products due to discoloration, and poor light resistance and tackiness. Another problem with the use of natural resins can be seen in their high tendency to crystallize, which leads to strong embrittlement after a short storage period of the products.

DESCRIPTION OF THE INVENTION

The invention aims to avoid these disadvantages and difficulties and has as its object to provide a thermoplastic composition which essentially contains biodegradable substances, but nevertheless has known properties in its properties, for example water resistance, rigidity, etc. synthetic nature is comparable or can be adapted to specific requirements. In particular, the problems that arise when using natural resins should be avoided. Furthermore, the thermoplastic composition should be easy to process with known means and have good mold release or mold separation.

The thermoplastic composition according to the invention contains a natural resin and a protein, the resin being a chemically modified natural resin.

In the context of the invention, the term “chemical modification” is understood to mean a change in the covalent (electron pair) bond of the natural resin, which is brought about by breaking existing or by forming new covalent bonds. However, this term does not include the formation of Salts, for example Ca or Zn resinates, comprise, since these are bonds of an ionic character in which the acid number can only be reduced to about 40 mg KOH / g. Modified resins in which the Modifying agent the original properties of the natural resin were changed so that its characteristics are largely similar to the basic properties of the modifying agent and can therefore be assigned to the synthetic resins.

Chemically modified natural resins have so far only been used as so-called tackifiers in the production of paints, for printing inks and in particular for adhesives ("adhesive resins"). These include tackifying substances with the aid of which adhesives can be formulated from suitable backbone polymers, ie the adhesive resins confer the Backbone polymers include adhesive, wetting, tackifying properties.

Surprisingly, it has been shown that mixing the two inherently sticky substances protein and natural resin can give non-sticky mixtures with good mold release properties. The chemical modification of the natural resins achieves a wider range of applications, oxidation stability and an extended temperature range. Furthermore, the acid number and the tendency of the natural resins to crystallize are reduced by the chemical modification. While the protein is not a thermoplastic substance per se, but when combined with liquids it only results in a very sticky dough, when mixed with the chemically modified natural resin it becomes a thermoplastic mass that repeatedly becomes liquid to pasty when heated and solidifies on cooling , The proteins also give the thermoplastic composition good dimensional stability so that finished parts do not warp and do not shrink. Since polypeptides have hydrophilic and hydrophobic side chains, the prerequisite for good compatibility with both hydrophilic polymers, for example starch, and with hydrophobic polymers, for example rubber or synthetic plastics, is given. Due to the free groups (-NH ₂ , -COOH, -OH, -SH) of the amino acids in the polymer chains of the proteins, the proteins can be modified, react with other components in the material or catalyze reactions. Alkali or slightly reducing agents can be used for the modification. The thermoplastic composition according to the invention can thus be varied over a wide range with regard to rigidity and elasticity.

The chemically modified natural resin component of the thermoplastic composition according to the invention advantageously brings about an increase in water resistance.

EP-B-0 712 428 discloses a thermoplastic molding which is based on a molding compound made from particles of a vegetable fiber material and which are embedded in a matrix of a biopolymer converted into a gel-melt-like state at elevated temperature and pressure, and on further additives based, the fibers are impregnated with a resin acid component. As the resin acid component, resin acids, such as those obtained when working up natural resins, resin acid derivatives and modified, e.g. resin acids esterified with polyols.

In addition to the fact that vegetable fibers are mandatory in this molding composition, resin acids obtained as a product from natural resins or modified resin acids are used as a further component. However, the thermoplastic composition according to the invention contains a chemical modified natural resin so that it is not necessary to extract resin acids from the natural resins.

For chemical modification, those reactions are suitable which give the natural resin sufficient light and oxidation resistance, possibly prevent further aerobic oxidation of the resin, and reduce the acid number of the natural resin to less than or equal to 30 mg KOH / g. In one embodiment of the invention, the chemically modified natural resin is non-polar. If necessary, the chemical modification is an esterification with a mono- or polyhydric alcohol; a di-oligo or polymerization; Hydrogenation, dehydrogenation; or a Diels-Alder reaction.

In one embodiment of the invention, the resin is a disproportionated, hydrogenated or polymerized rosin or a rosin derivative. This also includes resin esters, for example maleate resins, and resin alcohols.

Another embodiment is characterized in that the natural resin is a polyterpene. Polyterpenes include polymers based on naturally occurring cycloaliphatic compounds, e.g. To understand alpha-pinene or beta-pinene, which consist of (Cιo) units.

Of course, two or more chemically modified resins can also be used in the thermoplastic composition according to the invention.

In addition, individual resin acids, such as abietic, neoabietic, levopimaric, pimaric, isopimaric, palustric or dehydroabietic acid, are also to be counted as "natural resins" in the sense of the present invention.

Both vegetable proteins, preferably a concentrate with at least 50% protein content (N x 6.25) or an isolate with at least 70% protein content, for example proteins which are obtained as by-products in the starch industry, such as wheat gluten, corn protein, potato protein, are advantageously used as proteins , or proteins from the oil industry, such as rapeseed meal or legume proteins such as soy protein, as well as animal proteins, among which waste from the leather-producing industry, such as shavings and Glue leather, leather sanding dust, hair, wool, cotton, silk, or by-products from milk, blood and meat processing, such as collagens, gelatins and keratins, are to be understood. The leather waste is said to come from heavy metal-free tanning, preferably from vegetable tanning. Some animal proteins ("skieroproteins"), such as collagen or proteins made of leather, silk, hair or wool, have a linear structure with which they can give the thermoplastic mass strength through additional crosslinking. The tertiary structure of the proteins, which is stabilized by S-bridges, among other things, can be opened easily and reversibly, which makes the polymer chains easier to access and more densely packed, and thus a high strength or stiffness of the thermoplastic mass can be achieved.

Animal and vegetable proteins, for example leather and gluten, can also be used in combination. For example, the strength of the thermoplastic mass can be varied and adjusted with the proportion of animal proteins in the protein mixture. Mixtures of leather and vegetable protein also have a particularly good heat resistance, so that they are used in thermal forming, e.g. Injection molding, less shrinkage than masses with only animal protein content.

The mass ratio of chemically modified natural resin to protein is preferably between 1.0: 1.5 and 1.0: 4.0.

The thermoplastic composition can contain at least one filler. This can be from the known group of inorganic fillers, which are also used in plastics or in the paper industry. Suitable inorganic fillers are, for example, mica, kaolin, titanium dioxide, chalk, talc, etc. By adding graphite, a conductive material can be obtained without the thermoplastic composition becoming brittle due to the inorganic additive. These fillers are particularly advantageous in the production of very rigid products and also have an additional positive effect in mold separation.

However, fibers based on cellulose-containing materials, such as wood, man-made fibers, flax, hemp, coconut, etc., can also be used as fillers, especially if the product weight is low and the ash content in the In the event of thermal recycling to be achieved. Organic fillers bind water, reduce expansion and increase strength. The addition of resin-rich woods improves the swelling of the thermoplastic mass.

Elastomers, for example rubbers, which are in powder or granule form, are also possible as additives. Rubber latices are not so suitable as additives or fillers, since they are not very resistant to aging and, because of their emulsified or dispersed character, also introduce too much liquid into the overall mixture. With water contents of 5% or more in the total mass, there are already expansions due to foaming at the extruder nozzle and no dense granules are obtained.

The thermoplastic composition can also contain a modified rubber. By adding modified solid rubber, high elasticities and elongation values can be achieved. An additional effect is an increase in water resistance.

Among the synthetic elastomers are, for example, thermoplastic

Elastomers (TPE), especially based on styrene block copolymers, or styrene-butadiene rubber, are suitable as additives. Due to their high hydrophobicity, styrene block copolymers are well compatible with the thermoplastic composition according to the invention.

A semi-drying or drying oil, such as e.g. Linseed oil, optionally with a siccative, or a modified vegetable oil, e.g. epoxidized linseed oil added in the manufacture of the thermoplastic mass. This measure can also very well improve water resistance. Via the reactive group of the oils there is a connection to the proteins, which increases the hydrophobicity and prevents the oil from exuding.

The thermoplastic composition can also contain plasticizers, for example polyols such as glycerol or sorbitol, as further additives. These reduce the tendency to expand and lead to less bending-resistant products. Dyes and pigments, for example titanium oxide and / or biocides, can also advantageously be contained in the thermoplastic composition.

If necessary, further processing aids, such as lubricants, release agents, plasticizers, etc., which are known from plastics production, can be added to the thermoplastic composition according to the invention. To such

Processing aids include, for example, fatty acids and fatty acid derivatives such as hydrogenated fatty acids, amidated fatty acids, alkanolamides, metal soaps, e.g. Calcium stearate.

Depending on the fillers and additives or processing aids used, if appropriate, the proportion of protein and chemically modified natural resin can make up 20 to 90% by weight of the total mass in preferred embodiments of the invention, protein being 10 to 60% by weight and chemically modified resin can be contained to 10 to 30 wt .-% of the total mass.

To produce foamed, light parts from the thermoplastic mass, the water content must be increased accordingly. The equilibrium moisture at 50 wt .-% rel. Depending on the recipe, moisture and 23 ° C are around 2-5% by weight of water.

As a preferred embodiment, a thermoplastic composition is claimed with the proviso that it does not contain any vegetable fiber material.

The invention also relates to moldings which can be obtained by thermally deforming a thermoplastic composition according to the invention. Shaped bodies can be obtained, for example, by injection molding, casting, pressing, extruding, drawing or calendering a thermoplastic composition according to the invention.

The moldings can be in the foamed state.

To produce foamed, light parts from the thermoplastic mass, the water content must be increased accordingly. The equilibrium moisture at 50 wt .-% rel. Depending on the recipe, moisture and 23 ° C are around 2-5% by weight of water. The thermoplastic composition can be produced, for example, by combining the mixture of the individual substances, chemically modified natural resin, protein and, if appropriate, filler or additive (s) in a heatable kneader or an extruder, breaking them up or melting and, if appropriate, shaping them into granules become. Liquid, such as plasticizer or vegetable oil, can also be added during processing. To prevent degradation of the proteins, excessive temperatures and excessive shear should be avoided during processing. The processing can take place in a temperature range from 50 to 180 ° C, preferably between 80 and 130 ° C.

The possibly high initial moisture content of protein-rich raw materials can lead to foaming during extrusion, which is an obstacle to the production of compact, non-foamed articles. A suitable method for preventing foaming is degassing during extrusion. To do this, it is sufficient to open the extruder in a heated section and to allow the volatile constituents of the mass, in particular the water, to escape through the high temperature, the vacuum which may be applied and the intensive circulation of the screw.

In one embodiment of the manufacturing process, pelleting of the thermoplastic mass is provided prior to extrusion. For this purpose, the mass of beaters are pressed through a die, formed into endless strands and cut to the desired length with knives.

The thermoplastic composition according to the invention is very easily bindable to hydrophilic (e.g. leather) and hydrophobic (e.g. plastic) materials. Therefore, it is well suited for the back molding of fabrics.

The thermoplastic composition can be used in many fields of application. Injection molding can be used to produce toys, parts for the garden and the automotive industry, watch straps, fastening straps or clips in fruit and wine growing, as well as screw caps. By extrusion, films or sheets for further thermal Processing in the deep-drawing or pressing process, plates as sealing lips and much more can be produced.

The thermoplastic composition according to the invention is biodegradable and the moldings produced therefrom can be recycled.

EMBODIMENTS OF THE INVENTION

The invention is explained in more detail below with the aid of examples, the difference between the thermoplastic composition according to the invention and the prior art and the advantages of the invention being illustrated in the following examples and comparative examples.

Technical data for the examples:

Extrusion - production of granules:

Counter-rotating twin-screw extruders from Collin and Cincinnati and a co-rotating extruder from Werner Pfleiderer were used. The cylinder temperatures were between 30 and 175 ° C. If not explicitly described in the examples, the extruded strands were cooled in a water bath, dried with a blower and cut with a strand pelletizer.

Spray uss

The injection molding samples described in the following examples were produced on conventional Engel and Battenfeld injection molding machines. The cylinder temperature was 80-150 ° C, the injection pressure approx. 1000 bar, and a holding pressure adapted to the mixture was used. The tool temperature was 20 ° C. If not explicitly described in the examples, both the drawing in of the granules and the demolding of the injection molded parts were problem-free.

Physical measurements

The measurements were carried out on a universal testing machine from Frank. The puncture attempt is marked with a conical stamp spherical tip (diameter 10 mm) and a circular support (diameter 40 mm) measured. The penetration work is calculated from the maximum force and the path in the event of breakage. The tensile test is measured on shoulder bars according to DIN 53455. The specific tensile work results from the maximum force, the path at break and the cross-sectional area. The bending strength is determined according to DIN 53452.

In the examples or comparative examples 1 and 2, natural rosin or the calcium salt of rosin (calcium resinate) are compared with chemically modified non-polar natural resins. An esterified rosin and a polyterpene (made from and ß pinene) serve as examples of the chemically modified resins.

example 1

A mixture of 172.5 g of Dertoline ™ SG2 (esterified rosin, softening point 85 ° C), 250 g of Heyplast ™ NC 90 (granular natural rubber from Tiefenbacher), 300 g of mica and 327.5 g of wheat gluten is run in a counter-rotating twin-screw extruder at temperatures processed between 50 and 130 ° C. The melt temperature is 125 ° C, the melt pressure is 80 bar. The strands obtained are regular and of high strength. The strands are then granulated. The granulate is processed into test bars in an injection molding machine. The properties of the moldings obtained are summarized in Table 1.

Comparative Example 1

As example 1, except that 172.5 g of balsam resin (natural rosin, softening point 85 ° C.) are used instead of Dertoline ™ SG2. The strands obtained are irregular and of low strength. The strands cannot be pulled through the water bath and then granulated. The strand fragments are crushed manually for further processing on the injection molding machine. The strand fragments are processed into test bars in an injection molding machine. The pulling behavior is problematic. The properties of the moldings obtained are summarized in Table 1.

Example 2

As example 1, except that 172.5 g of Dercolyte ™ M115 (polyterpene from DRT, softening point 115 ° C., acid number less than 1 mg KOH / g) are used instead of Dertoline ™ SG2. The strands obtained are regular and of high strength. The strands are then granulated. The granulate is processed into test bars in an injection molding machine. The properties of the moldings obtained are summarized in Table 1.

Comparative Example 2

As example 1, except that 172.5 g of Erkazit ™ 10 (calcium resinate from Kraemer, softening point 110 ° C., acid number = 70-80 mg KOH / g) are used instead of Dertoline ™ SG2. The strands obtained are brittle and break easily. The strand fragments are then crushed manually. The strand fragments are processed into test bars in an injection molding machine. The properties of the moldings obtained are summarized in Table 1.

Table 1

The mixtures described in Comparative Examples 1 and 2 produce extremely fragile strands of low strength during extrusion and can therefore not be drawn through the water bath and then granulated. The injection molded parts made from it have low strength and are not elastic.

The mixtures described in Examples 1 and 2, on the other hand, give injection molded parts of high strength and elasticity. The specific tensile strength is used as a measure of the strength. The elastic behavior is described by means of repeated bending loads.

Examples and comparative examples 3-5 describe the influence of the protein on the stickiness of the extrudates and the shrinkage of the injection molded parts.

Example 3

A mixture of 100 g Dercolyte ™ M115 (polyterpene from DRT), 100 g PC 10 (powdered natural rubber from Weber and Schaer), 300 g mica and 200 g wheat gluten is in a counter-rotating twin-screw extruder at temperatures between 50 and 130 ° C processed. The melt temperature is 125 ° C, the melt pressure is 85 bar. The strands obtained are regular and of high strength. The strands are then granulated. The granulate is processed into test bars in an injection molding machine. The properties of the moldings obtained are summarized in Table 2.

Comparative Example 3

As in Example 3, except that double the amount of rubber and no protein are used. The mass pressure is 60 bar. The received

Strands are regular, highly elastic, but sticky. The strands can only be granulated using massive talc as a release agent. When stored, the granules clump relatively quickly despite the release agent. The granulate is processed into test bars in an injection molding machine. The pull-in behavior is problematic due to the stickiness of the granules. The properties of the moldings obtained are summarized in Table 2.

Example 4

A mixture of 100 g of Dercolyte ™ M115 (polyterpene from DRT), 130 g of mica and 200 g of wheat gluten is mixed in a counterflow

Twin screw extruder processed at temperatures between 50 and 130 ° C. The melt temperature is 125 ° C, the melt pressure is 90 bar. The strands obtained are regular and relatively brittle, but of high strength. The strands are then granulated. The granulate is processed into test bars in an injection molding machine. The properties of the moldings obtained are summarized in Table 2.

Comparative Example 5

Like Comparative Example 3, except that twice the amount of natural resin is used. The mass pressure is 36 bar. The strands obtained are regular and sticky. The strands cannot be granulated and processed even when using release agents.

Table 2

Examples 6 - 8 describe typical mixtures for the production of protein-containing thermoplastic materials. Proteins of animal as well as vegetable origin can be used. The mixture from example 7 contains an inorganic filler, the mixture in example 8 contains an organic filler.

Table 3 shows the values for the penetration work of conditioned samples ("before"; storage at 50% relative humidity and 23 ° C.) and wet samples ("after"; after storage of the previously conditioned samples in water for two hours). This shows the excellent water resistance of these patterns.

Example 6

A mixture of 325 g of Dercolyte ™ M115 (polyterpene resin from DRT), 500 g of PC 10 (powdered natural rubber from Weber & Schaer), 600 g of folded leather shavings (12% moisture) and 6 g of calcium stearate is added in a counter-rotating twin-screw extruder Temperatures between 50 and 130 ° C processed. The melt temperature is 130 ° C, the melt pressure is 130 bar. The strands obtained are then granulated. Granules are obtained which are suitable for further processing in injection molding machines, presses, extruders, etc. The granules are processed in an injection molding machine with 14 x 14 cm and 3 mm thick plate tools. The properties of the moldings obtained are summarized in Table 3.

Example 7

A mixture of 260 g of Dertoline ™ SG 2 (esterified rosin from DRT), 400 g of PC 10 (powdered natural rubber from Weber & Schaer), 600 g of mica, 800 g of wheat gluten and 20 g of titanium dioxide is added in a counter-rotating twin-screw extruder Temperatures between 50 and 130 ° C processed. The melt temperature is 125 ° C, the melt pressure is 40 bar. The strands obtained are then granulated. Granules are obtained which are suitable for further processing in injection molding machines, presses, extruders, etc. The granules are in an injection molding machine with a size of 14 x 14 cm and 3 mm thick plate tool processed. The properties of the moldings obtained are summarized in Table 3.

Example 8

As example 7, except that wood chips are used instead of mica. The properties of the moldings obtained are summarized in Table 3.

Table 3

Examples 9-12 illustrate the preparation more preferred

Embodiments of thermoplastic compositions according to the invention which have particularly good properties with regard to formability, water resistance, expandability and coloring.

Example 9

A mixture of 800 g Dercolyte ™ M115 (polyterpene from DRT), 500 g epoxidized linseed oil and 1500 g leather shavings is processed in a co-rotating twin screw extruder at temperatures between 50 and 130 ° C. The melt temperature is 125 ° C, the melt pressure is 14 bar. The strands obtained are regular and are then granulated.

Example 10

A mixture of 6550 g wheat gluten, 3450 g Dercolyte ™ M115, 5000 g Heypiast ™ NC 90, 6000 g kaolin, 100 g calcium stearate and 200 g titanium dioxide is in a counter-rotating twin screw extruder at temperatures between 50 and 140 ° C with a throughput of 20 kg / h extruded. In the second zone of the extruder, 1.13 kg / h of a mixture of glycerol / water (99: 1 part by weight) is pumped in by means of a liquid metering. The melt temperature is 130 ° C, the melt pressure 85 bar. Dense, unexpanded strands with high elasticity are obtained. The strands are granulated and can be processed accordingly.

Example 11

A mixture of 6550 g wheat gluten, 3450 g Dercolyte ™ M115, 5000 g Heypiast ™ NC 90, 6000 g kaolin, 100 g calcium stearate and 200 g titanium dioxide is in a counter-rotating twin screw extruder at temperatures between 50 and 140 ° C with a throughput of 20 kg / h extruded through a slot die with a lip width of 2 mm. In the second zone of the extruder, 1.13 kg / h of water are pumped in by means of a liquid metering, corresponding to a water content of 8.2% by weight. The melt temperature is 130 ° C, the

Melt pressure 85 bar. Foamed strips with a thickness of 4 mm and with good strength are obtained.

Example 12

A mixture of 260 g Dertoline SG ™ 2 (esterified rosin from DRT), 400 g PC 10 (powdered natural rubber from Weber & Schaer), 600 g mica, 800 g soy protein isolate and 45 g Solar Scarlet ™ 2G (direct dye from Clariant) is processed in a counter-rotating twin screw extruder at temperatures between 50 and 130 ° C. The melt temperature is 125 ° C, the melt pressure is 40 bar. The strands obtained are then granulated. Red granules suitable for further processing in injection molding machines, presses, extruders, etc. are obtained.

Examples 13 to 20 illustrate the outstanding suitability of the thermoplastic composition according to the invention for the production of a wide variety of moldings and its recyclability.

Example 13

The granules from Example 6 are melted in a counter-rotating twin-screw extruder and fed to a calender through a slot die (60 mm). Film strips with a thickness of 300 μm and good strength are obtained.

Example 14

The granules from Example 6 are melted in a counter-rotating twin-screw extruder and extruded through a slot die (300 mm) and placed on a conveyor belt. 3 mm thick flexible plates are obtained.

Example 15

According to Example 6, the granules are processed in an injection molding machine with a 14 x 14 cm and 3 mm thick plate tool. A 14 x 14 cm, 1 mm thick beech wood veneer is inserted into the side of the tool opposite the sprue. The veneer is thus back-injected. The adhesion of the thermoplastic mass to the veneer is excellent. In further tests, leather stains, plastic films, Lyocell ^® (cellulose fiber) tiles and polyester fabric pieces are inserted instead of the veneer. The adhesion to these materials is very good.

Example 16

A mixture of 2.5 kg Dercolyte ™ S 135 (polyterpene from DRT) and 4.2 kg Heypiast ™ NC 50 is kneaded to a homogeneous mass at a jacket temperature of 145 ° C. in a double Z kneader with a discharge screw. The The jacket temperature is reduced to 135 ° C., and 5.5 kg of shaved leather shavings (moisture 12%) are added. After a short time, a homogeneous thermoplastic mass is formed, to which 1.2 kg of Lyocell ^® fibers (15 dtex short cut 6 mm) are added. The fibers distribute themselves in the mass in a short time. It is then pressed out through the discharge screw through a perforated nozzle. These strands are passed through a heated calender and a film strip with a thickness of 1 mm is obtained.

Example 17

3000 g of Dercolyte ™ M115 (polyterpene from DRT) are melted at a jacket temperature of 130 ° C. in a double-Z kneader with a discharge screw. Then 6000 g of wheat gluten (moisture 12%) and 60 g of sodium sulfite are added. After a short time, a homogeneous thermoplastic mass is created. It is then pressed out through the discharge screw through a perforated nozzle. The strands are shredded and then pressed into translucent thin foils in a plate press.

Example 18

The film strips from Example 16 are processed into trays in a deep-drawing machine.

Example 19

Two 20 x 20 cm plates from Example 14 are heated on each surface with an IR radiator. These surfaces are then placed on top of each other and pressed in a Collin plate press with 10 bar hydraulic pressure. The resulting laminate has an excellent bond.

Example 20

The sprues from Example 15 are shredded and added to the granules from Example 1 by injection molding. Complete recycling is possible. Example 21

60 kg leather shavings with 8% water content, 29 kg maleated solid resin with an acid number of less than 25 mg KOH / g and a melting point of approx. 110 ° C (Erkamar ™ 2200 from Kraemer), 50 kg natural rubber (Neorub ™ 12F der Weber & Schaer), 1, 2 kg of Ca stearate and 4 kg of titanium oxide are dry mixed and melted in a counter-rotating, conical twin-screw extruder with connected wet granulation at a melt temperature of 165 ° C and formed into granules. The properties of the injection molded test specimens produced therefrom are shown in Table 4. The mixture is characterized by high elasticity.

Example 22

64 kg of leather shavings with 50% water content, 20 kg of maleated solid resin with an acid number of less than 25 mg KOH / g and a melting point of approx. 110 ° C (Erkamar ™ 2200 from Kraemer), 102 kg of wood shavings, 48 kg of corn meal 1 , 4 kg of Ca stearate and 3 kg of titanium oxide are mixed dry and melted in a single-screw extruder with hot cutting at a melt temperature of 150 ° C. and formed into granules. The properties of the injection molded test specimens produced therefrom are shown in Table 4. The mixture has very good strength values due to the high proportion of filler, but the swelling properties are unfavorable.

Example 23

60 kg leather shavings with 8% water content, 33 kg maleated solid resin with an acid number of less than 25 mg KOH / g and a melting point of approx. 130 ° C (Erkamar ™ 2300 from Kraemer), 22 kg thermoplastic elastomer (Thekaflex ™ der Fa. Schaefer Polymer), 0.8 kg Ca stearate and 2 kg titanium oxide are mixed dry and melted in a counter-rotating, conical twin-screw extruder at a melt temperature of 175 ° C. The strands do not expand and are cut into granules with a hot cut. The properties of those made from it Injection molded test specimens are shown in Table 4. The mixture is characterized by high bending stress with slightly reduced swelling.

Example 24

60 kg leather shavings with 8% water content, 33 kg maleated solid resin with an acid number of less than 25 mg KOH / g and a melting point of approx. 130 ° C (Erkamar ™ 2300 from Kraemer), 0.8 kg Ca stearate and 2 kg of titanium oxide are mixed dry and formed into pellets in a pelletizer (from Kahl) on a die with a 5 mm hole size. Leather shavings from dry leather sanding dust (moisture less than 10% by weight) have a very low bulk density and tend to clump together. In order to dose them, they are pre-pelleted. The pellets are mixed with 22 kg of thermoplastic elastomer (Thekaflex ™ from Schaefer Polymer) and 80 kg of wood shavings and extruded into a profile in a counter-rotating, conical twin-screw extruder at a melt temperature of 175 ° C. The profile is well formed, the properties of the test specimens cut out are comparable to those from Example 23.

Table 4

Example 25

A raw material mixture consisting of 65% by weight of shaved leather shavings (moisture 12% by weight), 22% by weight of fully esterified maleinated rosin (Erkamar ™ 2102; acid number less than or equal to 20 mg KOH / g), 12% by weight of natural rubber and 1% by weight of calcium stearate is processed into a strand by extrusion without degassing, the strand is then granulated and the granules are injection molded into test bars.

Example 26

A raw material mixture consisting of 65% by weight of leather shavings

(Moisture content 12% by weight), 22% by weight of fully esterified, maleinated rosin (Erkamar ™ 2102), 12% by weight of natural rubber and 1% by weight of calcium stearate is obtained by extrusion, the. In the second of three zones Mass is degassed, processed into a strand, the strand is then granulated and the granules are injection molded into test bars.

Table 5

Table 5 with the comparison of Examples 25 and 26 shows that the expansion can be prevented by degassing and the metering time of the injection molding machine in these examples thus drops from over 9 s to approx. 3 s.

The addition of polyalcohols and alkalis in Example 26 could improve the digestion of the leather and thus increase the tensile strength.

Example 27

A raw material mixture consisting of 62.5% by weight of shaved leather shavings (moisture 12% by weight), 21.2% by weight of fully esterified, maleated rosin (Erkamar ™ 2102), 11.5% by weight of natural rubber 0.9 % By weight of calcium stearate and 3.9% by weight of glycerol are processed into a strand by extrusion without degassing, the strand is then granulated and the granules are injection molded into test bars.

Example 28

A raw material mixture consisting of 62.5% by weight of folded leather shavings (moisture 12% by weight), 21.2% by weight of fully esterified, maleated

Rosin (Erkamar ™ 2102), 11.5% by weight of natural rubber, 0.9% by weight of calcium stearate and 3.9% by weight of glycerin is processed into a strand by extrusion with degassing in the second of three zones, the The strand is then granulated and the granules are injection molded into test bars.

Example 29

A raw material mixture consisting of 62.5% by weight of shaved leather shavings (moisture 12% by weight), 21.0% by weight of fully esterified, maleated rosin (Erkamar ™ 2102), 11.4% by weight of natural rubber, 0, 95% by weight of calcium stearate, 3.8% by weight of glycerol and 0.95% by weight of KOH are processed into a strand by extrusion without degassing, the strand is granulated and the granules are injection molded into test bars. Example 30

A raw material mixture consisting of 62.5% by weight of shaved leather shavings (moisture 12% by weight), 21.0% by weight of fully esterified, maleated rosin (Erkamar ™ 2102), 11.4% by weight of natural rubber, 0, 95% by weight of calcium stearate, 3.8% by weight of glycerol and 0.95% by weight of KOH is processed into a strand by extrusion with degassing in the second of three zones, the strand is granulated and the granules become Injection molded test rods.

Table 6

Claims

1. Thermoplastic composition containing at least one chemically modified natural resin and at least one protein.

2. Thermoplastic composition according to claim 1, wherein the chemical

Modification is a hydrogenation, dehydrogenation, esterification with an alcohol, a polymerization or a polymerization or a Diels-Alder reaction.

3. Thermoplastic composition according to claim 2, wherein the resin is a disproportionated, hydrogenated or polymerized rosin or a rosin derivative.

4. Thermoplastic composition according to claim 2, wherein the resin is a polyterpene.

5. Thermoplastic composition according to claim 1, wherein the resin has an acid number of less than or equal to 30 mg KOH / g.

6. Thermoplastic composition according to one of claims 1 to 5, characterized in that at least one animal protein is contained

7. Thermoplastic composition according to one of claim 6, characterized in that vegetable protein is additionally contained.

8. Thermoplastic composition according to one of claims 1 to 7, characterized in that the mass ratio of resin: protein is from 1.0: 1.5 to 1.0: 4.0.

9. Thermoplastic composition according to one of claims 1 to 8, characterized in that it additionally contains modified rubber.

10. Thermoplastic composition according to one of claims 1 to 8, characterized in that it additionally contains a thermoplastic polymer, preferably based on a styrene block polymer, or a styrene-butadiene rubber.

11. Thermoplastic composition according to one of claims 1 to 10, characterized in that it contains at least one filler.

12. Thermoplastic composition according to claim 11, characterized in that at least one filler is selected from the group consisting of mica, kaolin, titanium dioxide, talc, chalk and graphite.

13. Thermoplastic composition according to claim 12, characterized in that at least one organic filler is included.

14. A method for producing a thermoplastic composition, comprising the steps of: a) mixing at least one chemically modified natural resin with at least one protein; and subsequent b) combining, disintegrating or melting this mixture in a kneader or extruder.

15. The method according to claim 14, characterized in that step b) is carried out at a temperature of 50 to 180 ° C.

16. The method according to claim 14 or 15, characterized in that the mass is degassed in step b).

17. The method according to any one of claims 14 to 16, characterized in that in step a) or b) at least one component from the group consisting of plasticizer, lubricant, mold release agent, vegetable oil, glycerol or KOH is metered in.

18. The method according to any one of claims 14 to 17, characterized in that the thermoplastic composition is shaped into granules after step b).

19. Moldings obtainable by thermally deforming a thermoplastic

Composition according to one of Claims 1 to 13.

20. Shaped body according to claim 19, characterized in that it is in the foamed state.

1. Shaped body according to claim 19 or 20, characterized in that it is formed from a granulate according to claim 18.