TW201805349A - Polymer compounds comprising poly(meth)acrylimide foam particles - Google Patents

Abstract

The invention relates to a polymer compound comprising a thermoplastic resin and poly(meth)acrylimide (P(M)I) foam particles. The polymer compound of the present invention achieves better mechanical performance than the individual components, and can be widely used in lightweight constructions.

Description

Polymer mixture comprising poly(meth)acrylonitrile imine foam particles

The present invention relates to a polymer mixture comprising poly(meth)acrylonitrile imine (P(M)I) foam particles, especially polymethacrylimide (PMI) foam particles.

Poly (meth) Bing Xixi imide foam, such as poly foam Bing Xixi imine, such as a trademark by the marketing of Evonik Resource Efficiency GMBH as Rohacell ^® who, because of their light weight and high mechanical properties, so It is widely used in composite materials for lightweight design for use in aerospace, vehicle, sports and medical device industries.

Previously P(M)I foam systems were supplied in blocks, however they were not well suited for the processing of parts with complex three-dimensional geometries and could result in long cycle times, low precision, and waste of materials.

WO 2013/056947 describes a molding method of a P(M)I foam, which partially solves the above problems, wherein (pre-expanded) P(M)I polymer particles are bonded to the mold by a binder. Help foaming, the bonding The agent may be polyamine or poly(meth)acrylate. The amount of the binder may be up to 20% of the P(M)I polymer particles, that is, up to 16.7% based on the total weight of the P(M)I polymer particles and the binder. However, this method still results in long cycle times.

In order to solve the above problems, the inventors of the present invention have explored the possibility of forming a polymer mixture of P(M)I foam particles and a thermoplastic resin, and thus completed the present invention.

General description of the invention

The present invention provides a polymer mixture comprising: (1) a thermoplastic resin which is melt processable at a temperature lower than 400 ° C, and (2) poly(meth) acrylonitrile imide foam particles, It is maintained in a granular form at a temperature below 400 ° C, wherein the thermoplastic resin accounts for 20-99% based on the total weight of the polymer mixture, and the P(M)I foam particles account for 1 -80%.

Surprisingly, it has been found that in addition to being lightweight, the polymer blends of the present invention achieve better compression and/or flexural strength than individual components.

The present invention also provides a process for producing the polymer mixture of the present invention, which comprises the step of physically mixing the poly(meth)acrylonitrile imide foam particles with a melt of the thermoplastic resin.

The invention also provides the use of the polymer mixture of the invention for use in lightweight construction.

Detailed description of the invention

The thermoplastic resin is not limited as long as it is melt-processable at a temperature lower than 400 °C. Melt-processable is used herein in its conventional sense, that is, the polymer can be processed at a specified temperature without substantial degradation of the polymer.

Examples of the thermoplastic resin include polyamine, polyolefin, polyester, and a copolymer comprising any of the above fragments and blends thereof.

Preferably, the polyamine is selected from the group consisting of aliphatic polyamines, more preferably selected from the group consisting of PA6, PA11, PA12, PA46, PA66, PA10, PA610, PA612, PA1010, PA1012, and blends thereof.

The P(M)I foam particles used in the present invention can be obtained by granulation of a P(M)I foam which is not in a granular form.

The P(M)I foam is also referred to as a rigid foam and is characterized by its particular toughness. The P(M)I foam is usually produced in a two-stage process: a) producing a polymer for casting, and b) foaming the polymer for the mold. They are then cut or saw into the desired shape in accordance with the prior art.

The P(M)I foam is produced by the production of a monomer mixture comprising (meth)acrylic acid and (meth)acrylonitrile as a main component, and the molar is preferably 2 : 3 to 3: 2. Other comonomers may also be used, examples being esters of acrylic or methacrylic acid, styrene, maleic acid and methylene succinic acid and anhydrides thereof, and vinylpyrrolidone. However, the proportion of these comonomers should here not be higher than 30% by weight. A small amount of crosslinking monomer can also be used, an example being allyl acrylate. However, the amount thereof should preferably be at most 0.05% by weight to 2.0% by weight.

The copolymerization mixture also contains a blowing agent which decomposes or evaporates at a temperature of from 150 to 250 ° C and thus forms a gas phase. The polymerization is carried out below this temperature and the polymer for the mold thus contains a potential blowing agent. This polymerization is advantageously carried out in a block mold between two glass sheets.

The mold polymer is then foamed at a suitable temperature in the second step. The manufacture of such P(M)I foams is known in principle from the person skilled in the art and can be found, for example, in EP 1 444 293, EP 1 678 244 or WO 2011/138060.

The P(M)I foam particles used in the present invention can also be obtained by foaming P(M)I polymer particles.

The P(M)I polymer particles can be obtained by, for example, grinding the mold polymer in a cutter mill. Then, the abrasive body was foamed at a suitable temperature to produce P(M)I foam particles.

The P(M)I foam particles used in the present invention are preferably obtained by foaming P(M)I polymer particles, which are obtained by granulation via a P(M)I foam. Compared with the P(M)I foam particles, the closed foam chamber is not destroyed.

The P(M)I foam particles preferably have a particle diameter ranging from 0.1 to 30 mm, more preferably from 0.5 to 10 mm.

The P(M)I foam particles preferably have a bulk density of from 25 to 220 kg/m ³ , more preferably from 50 to 150 kg/m ³ .

In a preferred embodiment of the present invention, the P(M)I foam particles are polymethacrylimide (PMI) foam particles.

Mention may in particular be made of commercially available Rohacell ^® PMI polymers and/or foams from Evonik Resource Efficiency GMBH.

In the polymer mixture of the present invention, the ratio of the thermoplastic resin to the P(M)I foam particles is not limited.

The thermoplastic resin may comprise from 20 to 95%, preferably from 20 to 80%, more preferably from 30 to 70%, based on the total weight of the polymer mixture, and the P(M)I foam particles may comprise 5-80%, preferably 20-80%, more preferably 30-70%. However, based on the total weight of the polymer mixture, the thermoplastic resin may also be 1-99%, and the P(M)I foam particles may be 1-99%.

In a preferred embodiment of the present invention, the thermoplastic resin is melt processable at a temperature below 250 ° C, and/or the P(M)I foam particles are maintained at a temperature below 250 ° C. In the form of granules.

The polymer mixture of the present invention may include additives such as calcium carbonate, glass beads, zinc oxide, and fiber reinforcements such as ceramic fibers, polyarylene fibers, potassium titanate fibers, glass fibers, and carbon fibers, depending on the desired efficacy. Or depending on performance.

The polymer mixtures according to the invention are in principle generally suitable for use in any type of lightweight construction, and are particularly useful, for example, in the mass production of automobiles. Body construction or interior cladding in the industry, internal components in the rail vehicle construction or shipbuilding industry, aerospace industry, mechanical engineering, manufacture of sports equipment, furniture construction or wind turbine generator design.

Example

PMI foam particles used in the examples were prepared from PMI polymer particles marketed under the trademark ROHACELL ^® Triple F for Evonik Resource Efficiency GMBH. The PMI polymer particles are made from a fully polymerized copolymer sheet which is not pre-expanded by a granulator. The particles used in the examples were sieved to retain fine particles and had a particle size range of less than 1.0 mm. The PMI polymer particles have a bulk density of from about 600 to 700 kg/m ³ .

The PMI polymer particles are foamed in an oven at a temperature of 200-240 ° C for 30-60 minutes. PMI foam particles obtained having the 100-150kg / m ³ of bulk density and particle size of 0.5-5 mm.

The foam particles are PM.I and PA12 (manufactured by the Evonik Resource Efficiency GMBH Vestamid ^® L1600) PA12 and elastomer (manufactured by the Evonik Resource Efficiency GMBH Vestamid ^® E30, polyether block PA12) of melt mixing Two 50:50 by weight mixtures were prepared which were formed into sheets having a thickness of 5 mm.

The compressive strength (ISO 844) and flexural strength (ISO 178) and density of the panels were tested. The results are shown in the table below.

*Rohacell^® 200 WF PMI剛性發泡體，為來自Evonik Resource Efficiency GMBH之市售產品，於所行銷之Rohacell^®系列之PMI發泡體中，由於其之相當高抗壓及抗彎強度，而被選擇作為參考材料。

*Rohacell ^® 200 WF PMI rigid foam, a commercially available product from Evonik Resource Efficiency GMBH, is sold in the PHA foam of the Rohacell ^® series, which is highly resistant to compression and flexural strength. Selected as a reference material.

From the above it can be seen that a reduction of more than 25% is achieved for both Vestamid LI600 and Vestamid E30. Moreover, the polymer blends of these embodiments achieve higher compressive and/or flexural strength than individual materials.

Claims (11)

A polymer mixture comprising: (1) a thermoplastic resin which is melt processable at a temperature below 400 ° C, and (2) a poly(meth) acrylimide (P(M)I) a foam particle which is maintained in a granular form at a temperature lower than 400 ° C, wherein the thermoplastic resin accounts for 20-99% based on the total weight of the polymer mixture, and the P(M)I foam Body particles account for 1-80%. The polymer mixture of claim 1, wherein the thermoplastic resin is selected from the group consisting of polyamines, polyolefins, polyesters, and copolymers comprising any of the above fragments and blends thereof. The polymer mixture of claim 2, wherein the polyamine is selected from the group consisting of aliphatic polyamines, more preferably selected from the group consisting of PA6, PA11, PA12, PA46, PA66, PA10, PA610, PA612, PA1010, PA1012 and blends thereof. The polymer mixture according to any one of the preceding claims, wherein the P(M)I foam particles have a particle size ranging from 0.1 to 30 mm, preferably from 0.5 to 10 mm. The polymer mixture according to any one of the preceding claims, wherein the P(M)I foam particles have a bulk density of from 25 to 220 kg/m ³ , preferably from 50 to 150 kg/m ³ . The polymer mixture according to any one of the preceding claims, wherein the P(M)I foam particles are obtained by (1) a P(M)I foam which is not granular. Granulation, or (2) foamed P(M)I polymer particles. The polymer mixture according to any one of the preceding claims, wherein the P(M)I foam particles are polymethacrylimide (PMI) foam particles. A polymer mixture according to any one of the preceding claims, wherein the thermoplastic resin comprises from 20 to 95%, preferably from 20 to 80%, more preferably from 30% by weight based on the total weight of the polymer mixture. 70%, and the P(M)I foam particles account for 5 to 80%, preferably 20 to 80%, more preferably 30 to 70%. The polymer mixture of any one of the preceding claims, wherein the thermoplastic resin is melt processable at a temperature below about 250 ° C, and/or The P(M)I foam particles are maintained in a granular form at a temperature below 250 °C. A method of producing a polymer mixture according to any one of the preceding claims, which comprises the step of physically mixing the P(M)I foam particles with a melt of the thermoplastic resin. Use of a polymer mixture according to any one of claims 1 to 9 for a lightweight construction.