EP2265668A1

EP2265668A1 - Method for producing a phase-change material composition

Info

Publication number: EP2265668A1
Application number: EP09725735A
Authority: EP
Inventors: Klaus Fieback; Dirk Carsten BÜTTNER; Angelo SCHÜTZ; Stefan Reinemann
Original assignee: Rubitherm Technologies GmbH; Thueringisches Institut fuer Textil und Kunststoff Forschung eV
Current assignee: Rubitherm Technologies GmbH; Thueringisches Institut fuer Textil und Kunststoff Forschung eV
Priority date: 2008-03-26
Filing date: 2009-03-25
Publication date: 2010-12-29
Also published as: AU2009228817A1; US20110193008A1; CN102046715B; CA2719724A1; AU2009228817B2; JP2011515551A; KR20100139088A; WO2009118344A1; US8262925B2; DE102008015782A1; CN102046715A

Abstract

The invention relates to a method for producing a low-exuding preferably non-exuding polymer-bonded phase-change material composition containing phase-change material, characterised in that the phase-change material is liquefied, the liquid phase-change material is introduced into an extruder at a temperature of between 50° C and 130° C, however at least 20° C to 70° C above the melting point of the phase-change material into which the polymer is also introduced, wherein the extruder comprises mixing transport and holder elements and the introduction of the phase-change material into the extruder in the extrusion direction is performed after the polymer.

Description

Method of making a phase change material composition

The invention relates to a method for producing a Ausschwitzarmen, preferably ausschwitzfreien polymer-bonded and phase change material having phase change material composition.

Such methods and phase change materials have already become known in various embodiments. For example, reference is made to EP 0747 431 Bl, WO 98/12366, US 2006/0124892 A1, US 4,908,166 A1, US 2002/0105108 A1, US 2006/0124892 A1 and US 2005/0208286 A1. Suitable phase change materials are, in particular, salt-based phase change materials.

Many applications of polymer-bound phase change materials on a larger scale for the thermal management in thermoplastic fibers, sheets, granules, etc. have so far failed because the process method for the incorporation of non-encapsulated PCM materials on the one hand too complex (US 2002/0105108, US 2005/0208286) in that in a first step, the unencapsulated PCM was mixed in a low molecular weight, PCM-affine polymer and then incorporated in a subsequent step as a granulate intermediate via a melt compounding route in a single-screw extruder into a higher molecular weight polymer matrix. On the other hand, at higher levels of PCM in a polymer matrix, PCM component exudation occurred at higher temperature and pressure loads. To date, this exudation has been attempted by sealing the surfaces completely with aluminum foil against the leakage of the PCM component liquefied at the phase transformation point in the case of large-area articles of PCM polymer composites (plates) (US 2006/0124892). The use of PCM composite materials in the form of heat storage granules for thermal management in water-based heat storage boilers results in adhesions of the heat storage granules by surface PCM material. At high fill levels of PCM in a polymer matrix (weight percent percent of PCM> 60%), the mechanical strength of the PCM polymer composite-based products (plates, granules, other geometric shaped bodies) decreases sharply. To improve the thermal conductivity of the PCM composites, there was no lack of attempts to mineral additives such. As graphite, to add to accelerate the absorption and release of heat energy over time.

Based on the cited prior art, the invention has the object to provide a method for producing a sweat-poor, preferably sweat-free phase change material with increased mechanical strength and improved as possible heat resistance and / or improved thermal conductivity, which provides the desired success with favorable manufacturability.

A possible solution to this problem is given by a first inventive concept by the subject-matter of claim 1, wherein it is pointed out that the liquid or liquefied phase change material at a temperature between 50 ° and 130 ° C, but in any case 20 ° to 70 ° C above the Melting temperature of the phase change material is introduced into an extruder, in which the polymer or polymers are introduced, wherein the extruder kneading, conveying and baffle elements, and that the introduction of the phase change material in the extruder in the extrusion direction immediately after the introduction of the Polymer is carried out in an area in which a first intense kneading action has already taken place on the polymer. The phase change material is thus introduced into the extruder not only at a relatively high temperature, but also in a range in which the polymer material is already kneaded to some extent. And preferably in a first calming section, which is essentially only about the promotion of the material. Due to the high temperature of the phase change material are good fluid properties of the phase change material ensured during insertion. The polymers introduced (preferably polyethylene, in particular low-density polyethylenes, for example also diblock and triblock copolymers) act both as dispersion matrix and polymer matrix at the same time. Preferably additionally introduced polymer PMMA can act in particular as a viscosity promoter and synergistic component with an improved formation of a three-dimensional network of diblock and triblock copolymers in the PCM polymer composites and in particular both the Auswitzverhalten the PCM component of the PCM polymer composites at elevated temperature and Improve compressive stress, as well as improve the mechanical stability of the obtained molded body of the PCM polymer composite.

This results in improved cycle stability, i. an improved heat storage and heat dissipation behavior. In addition, improved thermal and mechanical properties result. The mechanical heat resistance is increased and the thermal conductivity is improved.

Although solid PCM materials with phase transition temperatures above 50 ^° C. can also be metered into the feed zone of the extruder, insufficient feed cooling of the feed zone can lead to problems of collection of the polymer components, as well as insufficient uniform, homogeneous distribution Ausschwitzfreie in situ encapsulation of the PCM component in the respective block copolymer matrix or in the Polymermatrbcblend from PMMA and block copolymers.

Carbon nanotubes, also called CNTs (English carbon nanotubes), are microscopic tubular structures (molecular nanotubes) made of carbon. The diameter of the tubes is usually in the range of 1 to 50μm, but it was which also produces tubes with a diameter of up to 0.4μm. Lengths of several millimeters for single tubes and up to 20cm for tube bundles have already been achieved. It is important that at least one of the dimensions (diameter) of the nanotubes is in the nano range and that the properties of these nanoparticles differ significantly from those of the same composition, but not with diameters in the nanometer range.

Surprisingly, it was found in experiments that the additional use of small amounts of carbon nanotubes (1-5 wt.%, Based on the extruder leaving the product), preferably multiwall carbon nanotubes already not only the in situ encapsulation of the PCM in the pure block copolymer or in the block copolymer / PMMA Blendmatrbc and thus further improves the Ausschwitzverhalten the PCM with increased pressure and temperature stress, but also increases the mechanical stability and the heat conductivity of the PCM polymer composites. For carbon nanotubes, for example, to the publication in "Labor &more" 04/07, p. 66 to 69 of the authors. Ralph Krupke, dr. Aravind Vijaraghavan, dr. Frank Hennrich and Prof. Horst Hahn referenced. The multi-wall carbon nanotubes also significantly improve the strand formation behavior (increase of the strand strength) of the polymer melt during discharge from the extruder and thus provide increased process reliability in the granulation stage of the melt-compounding route according to the invention. By expressing its own, nanostructured, secondary network, preferably based on the multiwall carbon nanotube with the affine PCM component within a submicron polymer network of the diblock or / triblock copolymers with PMMA and PCM, the PCM can exude Component at levels up to 80 wt% of PCM are completely or at least almost completely suppressed. The multi-walled carbon nanotubes used also have the role of inhibiting the PCM component from blooming out of the polymer composite, especially when liquid or liquefying PCM materials are already present in the polymer composites at room temperature or at human body temperature.

The multiwall carbon nanotubes already form a higher-viscosity network structure with liquid paraffin alone, which, in conjunction with the PMMA / block copolymer network, form an even denser network structure for encapsulated PCMs.

The phase change material used is preferably unencapsulated paraffin.

About practiced Schmelzecompoundierroute paraffinic PCM materials with phases may be prepared using the claimed polymers and additives of senumwandlungstemperaturen - be used 4 ° C to 80 ⁰ C.

By the in-situ polymer encapsulation of the PCM component (paraffin) within the formed PMMA / block copolymer network structure, up to 75% by weight of paraffin can be incorporated into the obtained polymer composites, which are still granulatable or directly from the extrusion melt by additional suitable equipment ( Slot die, trigger calender, spinnerets) to other shaped articles (plates, thick films, non-woven) can be processed.

Further features of the invention are explained below, also in the description of the figures, often in their preferred assignment to the above-discussed claim concept. But they can also be in an assignment to only one or more individual features of said claim concept or independent of meaning. Thus, it is first preferred that the extruder is a screw extruder, in particular a twin-screw extruder. Fig. 1 shows a preferred arrangement of the configuration of the screw elements, the peripheral dosing technique and the addition sites for the polymer components and the PCM again. The liquid or liquefied paraffin (5) is preheated in a melting and preheating vessel to the respective required addition temperature and metered with a feed pump (6) via a metering lance in an extruder, preferably twin-screw extruder.

Solid, flaky paraffin can be added via a metering balance (2) together with the respective polymer component (3) into the feed zone of the extruder. The PMMA component can be added via the polymer dosing scales (2) as well as the dosing trolley (3). Solid additives, such as, for example, claimed multiwall carbon nanotubes, are likewise metered into the feed zone of the extruder via a special powder dosing scale.

Furthermore, according to a preferred embodiment, the extruder can be operated at a speed of between 100 and 1200 revolutions per minute. Preferably between 300 and 1200 U / min, more preferably between 800 and 1200 U / min. According to the disclosure, these stated numerical bandwidths also include all intermediate values, in particular in steps of one revolution per minute. In this case, such a step can be made from the lower and / or upper limit to the respective other limit. With respect to the stated range, relatively higher speeds, in a desired short period of time, in particular a favorable intimate mixing of a block copolymer such as Kraton or Septon as an additive with, for example, PMMA as the second polymer matrix between the first conveying zone and reach the first kneading zone, which is also a prerequisite for a subsequent intimate mixing with the phase Changing material, especially paraffin, in subsequent conveyor and Knetzonen.

The residence time begins with a feed of the polymer (s) and of the additives which are initially and preferably fed simultaneously. In any case, the residence time but begins with entry of the later-fed component regarding polymer or additive. These are intimately mixed already in the first conveying zone, before the phase change material such as paraffin is added.

It is also preferred that a residence time of the melt in the extruder, based on the polymer matrix or then the mixture of the polymer matrix with the phase change material, is between one and four minutes. All intermediate values, in particular in one-second increments, are also included in the stated numerical bandwidth of the residence time. In this case, the intermediate values from the lower and / or upper limit to the respective other limit can provide a restriction.

As the polymer material very diverse materials can be used, for example LDPE (Low Density Polyethylene), HDPE (High Density Polyethylene), LLDPE (Linear Low-Density Polyethylene), polymethyl methacrylate and di- and triblock Coplymere based on the co-monomers Ethylene, styrene and butadiene and others.

Preferably, as much of the polymeric material is further added to the extruder as 10% to 40% of the final phase change material composition achieved. In the final product achieved, the phase change material composition, 10 to 40 percent by weight is then the polymer matrix. With regard to the introduction of the polymer material, in turn, all intermediate values, in particular in 1/10 steps, in the revelation included. Such a step may restrict said bandwidth from the lower and / or upper limit to the other limit.

Furthermore, it is preferred that additives are added. The introduction of the phase change material is carried out so far preferably after the introduction of the matrix polymer and the additive, in a region in which already a first kneading action has taken place on the mixture of polymer and additive.

In particular, in an amount of 1-20 percent by weight based on the prepared phase change material composition. Also in this regard, all intermediate values, in particular in 1/10 weight percent steps included. This means that the mentioned bandwidth can be limited 1/10 percentage steps from the lower and / or upper limit to the other limit.

An additive may be given in particular by a block co-polymer. As such, for example, styrene copolymers such as SEBS, SEEPS and SBS come into question. Further, in particular, the known under the trade names Kraton-G and Septon copolymers. Also propylene block copolymers such as EPR.

Another preferred additive is seen in carbon nanotubes. Specifically, for example, MWCNT (Multi Wall Carbon Nanotubes) and SWCT (Single Wall Carbon Nanotubes) can be used, with and without chemical modification. These are nanostructures with a length to diameter ratio of 1: 100 to 1: 1000 and more, possibly up to 1: 1,000,000 or more. They are formed by cylindrical carbon lenstoff molecules. In the given areas, all intermediate values are also included in increments of increments, be it as a restriction of the area from above and / or from below.

The residence time of the materials in the extruder is more preferably provided in such a way that a residence time of 2 minutes is at any rate not undershot. Thus, a residence time in the range of 2 to 5 minutes is preferred, whereby all intermediate values, in particular in one-second increments, are also included in this bandwidth. This means in steps from the lower and / or upper limit to the other limit.

It is further preferred that the temperature in the extruder is adjusted so that it is at least 20 ° C -180 ° C, preferably 50 ° C -150 ° C above the feed temperature of the phase change material. These intermediate temperature ranges also include all intermediate values, in particular in 1 ° C increments. This is also such that such a step can be made from the lower or upper limit to the respective other limit.

In addition, it is preferable that the obtained phase change material composition has a content of the phase change material of 60% or more, particularly 70% or more, more preferably 75% or more, up to 80%, with more preferably a range of 65-75 % is. Here, too, all intermediate values, in particular in 1/10 percentage steps, are included in the disclosure, so that the phase change material can also be provided of 60.1% or more, etc. In particular, the intermediate values also refer to limitations of the respectively specified areas, be it from above and / or from below. EXAMPLES

example 1

In a twin-screw extruder ZSK25 (COPERION company) with a length-to-diameter ratio of 40: 1, hot phase change material (Paraffin RT58 from Rubitherm Technologies GmbH) at a temperature of .mu.m was introduced into the screw zone between the first kneading zone and the second conveying zone via a hermetically sealing metering lance 120 ° C in a melt stream consisting of PMMA (carrier polymer) and phase-compatibilizing additive (SEBS or trade name Kraton G 1651) fed. By means of a screw speed of 1000 rpm and a total throughput of PMMA / Kraton G 1651 / RT58 of 5 kg / h, an average residence time of 2.5 minutes was achieved. The required homogeneous mixing of all three feed components was achieved. The first two zones of the extruder were set to a temperature of 260 ° C and 250 ° C, respectively.

The phase change material composition achieved was:

75 percent by weight PCM (Rubitherm RT 58, Rubitherm Technologies GmbH)

15 weight percent SEBS (Kraton G 1651) - 10 weight percent PMMA.

After passing through a sufficiently adjusted water cooling section, a stable strand could be formed, pulled, and granulated from the melt discharge nozzle. The granules obtained had a DSC (differential scanning calorimetry, heat calorimetric measurement method for determination of melting point). and crystallization points of materials) has a phase change enthalpy of 135 J / g. The phase change material composition exhibited very good cycle stability and proved to be very resistant to exudation of the water in dry and dry media in relevant tests simulating 30 cycles of thermal cycling (20 ° C <-> 85 ° C) Phase change material (paraffin).

A sample of these granules was further an extraction test subject water mixture with 50 weight percent (parts by mass of water to mass of ethylene glycol) at 30 nacheinanderf olgenden temperature cycles between 30 ⁰ C and 105 ⁰ C in an E thylenglykol /, whereby in each case a heating and cooling cycle 8 h lasted , The extract solution was transparent. The content of paraffin in the ethylene glycol / water extract solution was determined to be <50 ppm. The granules did not stick together when hot or when cooled.

Example 2

In a twin-screw extruder ZSK25 (COPERION company) with a 1 / d ratio of 40: 1 hot PCM (paraffin RT58 from Rubitherm Technologies GmbH) with a temperature of 120 ° were via a hermetically sealing metering lance in the screw zone between the first Knetzone and second conveying zone C is fed into a melt stream consisting of PMMA (carrier polymer) and phase-compatibilizing additive (SEEPS (Septon ™ 4055, KURARAY Co. Ltd.) through a screw speed of 1000 rpm, a total throughput of PMMA / KRATON G 1651 / RT58 from 5 kg / h, a mean residence time of 2.5 minutes was set for the required homogenization of all three feed components The first two zones of the extruder were set to a temperature of 270 ° C or 265 ° C. The phase change material composition achieved was as follows:

- 60% by weight PCM (Rubitherm RT 58, Rubitherm Technologies GmbH) - 15% by weight SEEPS (Septon ™ 4055, KURARAY Co. Ltd)

- 25 weight percent PMMA.

After passing through a sufficiently adjusted water cooling section, a very stable strand could be formed, drawn and granulated from the melt discharge nozzle. The obtained granules had a phase change enthalpy of 100 J / g in the DSC. The polymer support PCM material exhibited very good cycle stability and proved to be very resistant to exudation in both water and dry media in relevant tests simulating 30 cycles of thermal cycling (20 ° C -> 85 ° C) of the PCM (paraffin).

A sample of this granulate was further subjected to an extraction test in an ethylene glycol / water mixture with 50% by weight (parts by weight of water to parts by weight of ethylene glycol) at 30 successive Tempe- cycles between 30 ⁰ C and 105 ⁰ C, each with a heating and cooling 8 h took. The extract solution was transparent. The content of paraffin in the ethylene glycol / water extract solution was determined to be <50 ppm. The granules did not stick together in both the hot and the cooled state.

Both the granules obtained and the injection-molded products made therefrom (test plates) had a significantly improved heat distortion resistance. Example 3

In a twin-screw extruder ZSK25 (COPERION company) with a 1 / d ratio of 40: 1 hot PCM (paraffin RT58 from Rubitherm Technologies GmbH) with a temperature of 120 ° were via a hermetically sealing metering lance in the screw zone between the first Knetzone and second conveying zone C in a melt stream consisting of LLDPE (carrier polymer) and phase-compatibilizing additive (Multiwall-Carbon Nanotubes, NANOCYL SA Belgium) fed. By a screw speed of 1000 rpm, a total throughput of LLDPE / MWCNT / RT58 of 5 kg / h was a mean residence time of 2.5 minutes for the required homogenization of all three

Insert components set. The first two zones of the extruder were set at a temperature of 220 ° C. The phase change material composition was as follows:

60 percent by weight PCM (Rubitherm RT 58, Rubitherm Technologies GmbH)

4% by weight SEBS (MWCNT, NANOCYL S.A.) 36% by weight LLDPE.

After passing through a sufficiently adjusted water cooling section, a very stable and very smooth strand could be formed, drawn and granulated from the melt discharge nozzle.

Other examples that gave a reasonable but not optimal result:

Example 4

In a twin screw extruder ZSK25 (COPERION company) with a 1 / d ratio of 40: 1 was over a hermetically sealed metering lance in the screw zone between the first Knetzone and second conveying zone hot PCM (Paraffin RT58 from Rubitherm Technologies GmbH) at a temperature of 120 ° C. in a melt stream consisting of the carrier polymer SEBS (Cone G 1651). By means of a screw speed of 1000 rpm, a total throughput of Kraton G 1651 / RT58 of 5 kg / h, an average residence time of 2.5 minutes was set for the required homogenization of the two feed components. The first two zones of the extruder were set to a temperature of 270 ° C and 260 ° C, respectively. The phase change material composition achieved was as follows:

65 percent by weight PCM (Rubitherm RT 58, Rubitherm Technologies GmbH)

35% by weight SEBS (Kraton G 1651).

After passing through an adequately adapted water cooling section, a stable strand of very elastic and sticky nature could be attracted and granulated from the melt discharge nozzle. The obtained granules according to this recipe had a phase change enthalpy of 112 J / g in the DSC. Polymer support PCM material exhibited very good cycle stability and was still satisfactory in swirling simulations of temperature-cycling simulations (20 ° C - + 85 ° C). However, at a temperature above 95 ° C and at the same time slight compressive stress, the PCM exuded.

Example 5

In a twin-screw extruder ZSK25 (COPERION company) with a 1 / d ratio of 40: 1 hot PCM (paraffin RT58 from Rubitherm Technologies GmbH) with a temperature of 120 ° was via a hermetically sealing metering lance in the screw zone between the first Knetzone and second conveying zone C in a melt stream consisting of the LLDPE (carrier polymer) and phase-compatibilizing additive SEBS (Kraton G 1651). By means of a screw speed of 1000 rpm, a total throughput of Kraton G 1651 / RT58 of 5 kg / h, an average residence time of 2.5 minutes was set for the required homogenization of these three feed components. The first two zones of the extruder were set at a temperature of 220 ° C. The phase change material composition was as follows:

- 70 percent by weight PCM (Rubitherm RT 58, Rubitherm Technologies GmbH)

15 weight percent SEBS (Kraton G 1651) - 20 weight percent LLDPE.

After passing through a sufficiently adjusted water cooling section, a stable strand could be formed, attracted and granulated from the melt discharge nozzle. The obtained granules according to this recipe had a phase change enthalpy of 135 J / g in the DSC. While the polymer support PCM material exhibited very good cycle stability, it was found to be inconsistent with PCM (paraffin) exudation in simulations of multiple temperature load cycles (20 ° C - + 85 ° C) ). The sweating occurred in particular when at the same time as the test temperature of 85 ° C still a pressure load occurred.

The invention also provides a polymer-bound phase change material composition with a proportion of phase change material and carbon nanotubes as additive. As polymer materials, one or more of the aforementioned materials may be included, also with regard to the proportions already mentioned above. With regard to possible further additives, which may be provided in any case supplementary, is also referred to above Revelation directed. Also with regard to the carbon nanotubes reference is made to the details explained further above.

Overall, in the case of the methods described or relates to said polymer-bound phase change material composition granules, which can be used for further processing, in particular in the plastic injection process.

Below, the invention is further explained with reference to the accompanying drawings, but in which only exemplary embodiments are shown. In detail shows:

Figure 1 shows schematically the arrangement suitable for carrying out the method.

Fig. 2 is a schematic representation, enlarged, of leakproof recorded paraffin domains in the network of styrene / ethylene / butadiene block copolymers and PMMA;

3 shows a microscope image of a paraffin-PMMA / SEBS copolymer blend, in an enlargement in which 6 mm in the illustration corresponds to 100 μm;

4 shows a reproduction according to FIG. 3, in which 7 mm in the reproduction correspond to 10 μm;

5 shows a reproduction according to FIG. 3 or FIG. 4, in which 3 mm corresponds to 1 μm in the reproduction; 6 shows a reproduction according to FIGS. 3 to 5, in which 4 mm in the reproduction correspond to 20 μm;

7 shows a reproduction according to FIGS. 3 to 6, in which 3 mm in the reproduction correspond to 20 μm;

8 shows a reproduction according to FIGS. 3 to 7, in which 4 mm in the reproduction correspond to 20 μm.

Referring to Fig. 1, a twin-screw extruder 1 is shown, which is shown in side view.

At the beginning of the extruder section, in a first conveying zone a, the polymer is introduced from a supply container 2, in the exemplary embodiment PMMA.

At the same time or in the conveying direction, if necessary downstream, an additive 3 is introduced, in the embodiment SEBS.

In the conveying direction much later, namely after a first kneading path, which is denoted by b, liquid phase change material 5, namely in this case paraffin, is introduced via a nozzle 4. 6 denotes a heatable liquid metering pump.

The introduction takes place in the second conveying zone with storage zone c, downstream of the first kneading zone b.

After the conveying zone with congestion zone c is followed by a second Knetzone d, which in turn with a third conveying zone e, a third Knetzone f, a fourth conveying zone g and another Knetzone with stowage zone h and a discharge section i alternates. 7 indicates a heating of the storage container 8 for the liquid PCM.

After leaving the extruder 1, the resulting phase change material composition passes through a water bath 9 and then a granulation 10. The granules obtained are taken up in a granule collecting container 11.

A desired dense polymeric network structure is mainly characterized, obtains that in the first kneading zone (b), the second conveying zone (c) and the second kneading zone (d) a very high melt temperature of preferably from 50 ⁰ C - 150 ° C above the feed temperature PCM is sought, the phase change material is preferably added in liquid form at a temperature of 50 ⁰ C to 130 ° C above the melting temperature of the PCM itself, a high shear rate by screw speeds of 500 - 1200 U / min is applied and residence times of Melt in the extruder from 1 to 4 minutes. Longer residence times above 4 minutes are possible but not advantageous because the low throughputs of PCM polymer composites are not a cost effective manufacturing process. Although residence times of less than 1 minute and / or high throughput rates are possible, the homogeneous incorporation of the phase change material in the insufficiently formed polymer network structure is severely impaired, so that free, unbound phase change material then exits the extruder and, in addition, can not be granulated Polymer composite strand is obtained more.

The stowage elements arranged according to FIG. 1, or more generally a stowage effect, provide the desired effect of an extended residence time of the PCM polymer composite melt in the extruder of preferably 2 minutes or more, in particular up to 5 minutes, whereby also in this case all intermediate values, especially in one-second increments, be it restrictive from above and / or from below with respect to an area.

FIG. 2 schematically illustrates how the PCM domains 12 (here paraffin) are formed into the network structure of the rigid styrene-13 and elastic butadiene block constituents 14 of the SEBS block copolymer (Kraton 1651) and the rigid PMMA segments 15 embedded present. The PMMA segments 15 form annular structures within which, but also overlying, the network structures of the coupled rigid styrene components 13 and elastic butadiene block components 14 are embedded. Within a network mesh are a flagship of PCM domains 12.

The following FIGS. 3 to 8 are various SEM images of a paraffin-PMMA / SEBS copolymer blend obtained after Kryobruch on the granules obtained in Example 1. To achieve this representation, the sample was deep-frozen and exposed to such high mechanical loads that a break occurred due to the cold-related high rigidity (Kryobruch). It can be seen from FIGS. 4 and 5 that the PMMA / block copolymer polymer network structure formed encloses the paraffin domains on all sides in such a way that they can no longer emerge from the network network, since even some apparently isolated paraffin domains already exist in their interior own the PMMA / Block networks. Most clearly, the manifestation of the paraffin / PMMA / block copolymer network structure can be seen in FIGS. 7 and 8.

All disclosed features are essential to the invention. The disclosure content of the associated / attached priority documents (copy of the prior application) is hereby also incorporated in the disclosure of the application. also included for the purpose of including features of these documents in claims of the present application.

Claims

claims

1. A process for producing a Ausschwitzarmen, preferably non-sweating polymer-bound and phase change material having phase change material composition, characterized in that the phase change material is liquefied, that the liquid phase change material at a temperature between 50 ° C and 130 ° C, but at least 20 ° C to 70 ° C above the melting point of the phase change material, is introduced into an extruder, in which the polymer is introduced, wherein the extruder kneading, conveying and baffle elements and that the introduction of the phase change material in the extruder in the extrusion direction is carried out after the polymer.

2. The method according to claim 1 or in particular according thereto, characterized in that the phase change material is introduced in the non-encapsulated state.

3. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the phase change material is introduced with up to 80 wt.% In the matrix material used as polymer material.

4. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the introduction of the phase change material is carried out in a single process stage for the purpose of intimate mixing with the polymer.

5. The method according to claim 1 or in particular according thereto, characterized in that the introduction of the phase change material into the extruder is carried out in a region which comprises an end region of a first kneading zone and an initial region of a subsequent conveying zone of the extruder.

6. The method of claim 1 or in particular according thereto, characterized in that phase change material (paraffin) is incorporated with phase transition temperatures of -4 ° C to 80 ° C in the polymer matrix network structure.

7. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the extruder is a screw extruder, preferably a twin-screw extruder.

8. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the extruder is operated at a speed between 500 and 1200 U / min.

9. The method according to one or more of the preceding claims or in particular according thereto, characterized in that a residence time of a melt in the extruder is between 1 and 4 minutes.

10. The method according to one or more of the preceding claims or in particular according thereto, characterized in that is used as the polymer LDPE, HDPE and / or LLDPE.

11. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the polymer PMMA (Polymethyl Methaαylat) is used to improve the in-situ generated polymer encapsulation of the PCM component and to improve the mechanical performance and heat resistance;

12. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the total amount of the polymers used are added to a formulation in an amount per unit time, resulting in a composition with 10 to 40 weight percent total content of polymers of the obtained

Phase change material composition leads.

13. The method according to one or more of the preceding claims or in particular according thereto, characterized in that one or more polymeric and / or inorganic additives are added.

14. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the additives are added in an amount corresponding to 1 to 20 weight percent of the obtained phase change material composition.

15. The method according to one or more of the preceding claims or in particular according thereto, characterized in that an additive is a polymeric block copolymer.

16. The method according to one or more of the preceding claims or in particular according thereto, characterized in that is added as a polymeric additive SEBS, SEEPS, EPR and / or SBS.

17. The method according to one or more of the preceding claims or in particular according thereto, characterized in that multiwall carbon nanotubes are added as an inorganic additive for improving the formation of the PCM / polymer / additive network structure and increasing the thermal conductivity of the -CM / Polymercomposites.

18. The method according to one or more of the preceding claims or in particular according thereto, characterized in that an average residence time of the melt of 2 minutes is not exceeded.

19. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the temperature in the

Extruder is set so that it is at least 20 ° C to 180 ° C, preferably 50 ° C to 150 ° C above the feed temperature of the PCM.

20. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the obtained phase change material composition has a PCM degree of sense of 60

Percent by weight or more.

21. Polymer-bound phase change material composition with a proportion of phase change material and carbon nanotubes as an additive.

22. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the obtained at the extruder outlet PCM polymer composite melt without Zwischengranulierung immediately by appropriate adapter nozzles and peripheral equipment to plates, thin-rolled films, fibers and non-wovens is further deformed ,

23. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the phase change material has a phase change temperature in the range of -4 ° C to 80 ° C.

24. The method according to one or more of the preceding claims or in particular according thereto, characterized in that polymers and / or inorganic additives are added.

25. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the exiting at the extruder exit PCM polymer composite melt without

Intermediate granulation readily to plates, thin rolled films, fibers or non-wovens is further deformed.

26. Polymer-bonded phase change material composition with a proportion of phase change material and carbon nanotubes as additive.