PL3717211T3 - Tworzywa piankowe wysokotemperaturowe o zmniejszonym wchłanianiu żywicy do wytwarzania materiałów przekładkowych - Google Patents

Tworzywa piankowe wysokotemperaturowe o zmniejszonym wchłanianiu żywicy do wytwarzania materiałów przekładkowych

Info

Publication number
PL3717211T3
PL3717211T3 PL18803993.7T PL18803993T PL3717211T3 PL 3717211 T3 PL3717211 T3 PL 3717211T3 PL 18803993 T PL18803993 T PL 18803993T PL 3717211 T3 PL3717211 T3 PL 3717211T3
Authority
PL
Poland
Prior art keywords
materials
preparation
high temperature
resin absorption
sandwich
Prior art date
Application number
PL18803993.7T
Other languages
English (en)
Inventor
Christian Trassl
Thomas Richter
Original Assignee
Evonik Operations Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Evonik Operations Gmbh filed Critical Evonik Operations Gmbh
Publication of PL3717211T3 publication Critical patent/PL3717211T3/pl

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C67/00—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00
    • B29C67/20—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00 for porous or cellular articles, e.g. of foam plastics, coarse-pored
    • B29C67/205—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00 for porous or cellular articles, e.g. of foam plastics, coarse-pored comprising surface fusion, and bonding of particles to form voids, e.g. sintering
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/3415—Heating or cooling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/3415—Heating or cooling
    • B29C44/3426—Heating by introducing steam in the mould
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/36—Feeding the material to be shaped
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/36—Feeding the material to be shaped
    • B29C44/38—Feeding the material to be shaped into a closed space, i.e. to make articles of definite length
    • B29C44/44—Feeding the material to be shaped into a closed space, i.e. to make articles of definite length in solid form
    • B29C44/445—Feeding the material to be shaped into a closed space, i.e. to make articles of definite length in solid form in the form of expandable granules, particles or beads
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/56—After-treatment of articles, e.g. for altering the shape
    • B29C44/5627—After-treatment of articles, e.g. for altering the shape by mechanical deformation, e.g. crushing, embossing, stretching
    • B29C44/5636—After-treatment of articles, e.g. for altering the shape by mechanical deformation, e.g. crushing, embossing, stretching with the addition of heat
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
    • B29C44/34—Auxiliary operations
    • B29C44/58—Moulds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/22—After-treatment of expandable particles; Forming foamed products
    • C08J9/228—Forming foamed products
    • C08J9/232—Forming foamed products by sintering expandable particles
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/36—After-treatment
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L81/00—Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing sulfur with or without nitrogen, oxygen or carbon only; Compositions of polysulfones; Compositions of derivatives of such polymers
    • C08L81/06—Polysulfones; Polyethersulfones
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2079/00—Use of polymers having nitrogen, with or without oxygen or carbon only, in the main chain, not provided for in groups B29K2061/00 - B29K2077/00, as moulding material
    • B29K2079/08—PI, i.e. polyimides or derivatives thereof
    • B29K2079/085—Thermoplastic polyimides, e.g. polyesterimides, PEI, i.e. polyetherimides, or polyamideimides; Derivatives thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2081/00—Use of polymers having sulfur, with or without nitrogen, oxygen or carbon only, in the main chain, as moulding material
    • B29K2081/06—PSU, i.e. polysulfones; PES, i.e. polyethersulfones or derivatives thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
    • B29K2105/04—Condition, form or state of moulded material or of the material to be shaped cellular or porous
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/30—Vehicles, e.g. ships or aircraft, or body parts thereof
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2203/00—Foams characterized by the expanding agent
    • C08J2203/22—Expandable microspheres, e.g. Expancel®
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2205/00—Foams characterised by their properties
    • C08J2205/10—Rigid foams
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2379/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen, or carbon only, not provided for in groups C08J2361/00 - C08J2377/00
    • C08J2379/04—Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
    • C08J2379/08—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2381/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing sulfur with or without nitrogen, oxygen, or carbon only; Polysulfones; Derivatives of such polymers
    • C08J2381/06—Polysulfones; Polyethersulfones

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
  • Laminated Bodies (AREA)
  • Molding Of Porous Articles (AREA)
PL18803993.7T 2017-11-27 2018-11-20 Tworzywa piankowe wysokotemperaturowe o zmniejszonym wchłanianiu żywicy do wytwarzania materiałów przekładkowych PL3717211T3 (pl)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP17203684 2017-11-27
PCT/EP2018/081839 WO2019101703A1 (de) 2017-11-27 2018-11-20 Hochtemperaturschaumstoffe mit verringerter harzaufnahme zur herstellung von sandwichmaterialien

Publications (1)

Publication Number Publication Date
PL3717211T3 true PL3717211T3 (pl) 2023-05-02

Family

ID=60515134

Family Applications (1)

Application Number Title Priority Date Filing Date
PL18803993.7T PL3717211T3 (pl) 2017-11-27 2018-11-20 Tworzywa piankowe wysokotemperaturowe o zmniejszonym wchłanianiu żywicy do wytwarzania materiałów przekładkowych

Country Status (17)

Country Link
US (1) US11485832B2 (pl)
EP (1) EP3717211B1 (pl)
JP (1) JP7263352B2 (pl)
KR (1) KR102701369B1 (pl)
CN (1) CN111819069B (pl)
AU (1) AU2018373661B2 (pl)
BR (1) BR112020010391B1 (pl)
CA (1) CA3083397A1 (pl)
DK (1) DK3717211T3 (pl)
ES (1) ES2939295T3 (pl)
IL (1) IL274860B1 (pl)
MX (1) MX2020005293A (pl)
PL (1) PL3717211T3 (pl)
SG (1) SG11202004813YA (pl)
TW (1) TWI776999B (pl)
WO (1) WO2019101703A1 (pl)
ZA (1) ZA202003629B (pl)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102005005437A1 (de) 2005-02-05 2006-08-10 Eppendorf Ag Filterpipettenspitze
US20200207939A1 (en) 2017-08-24 2020-07-02 Evonik Operations Gmbh PEI particle foams for applications in aircraft interiors
DE102020204875A1 (de) 2020-04-17 2021-10-21 Volkswagen Aktiengesellschaft Verfahren zur Herstellung eines Partikelschaum-Formkörpers
JP2023547244A (ja) 2020-10-29 2023-11-09 エボニック オペレーションズ ゲーエムベーハー フォームフィルムの製造用のフォームパネルを製造する方法
EP4155046A1 (en) * 2021-12-23 2023-03-29 SABIC Global Technologies B.V. Foamed assembly

Family Cites Families (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4842713B1 (pl) * 1963-10-29 1973-12-14
JPH0698696B2 (ja) * 1988-04-15 1994-12-07 東洋機械金属株式会社 熱可塑性合成樹脂ブロック用発泡成形方法
US4960549A (en) * 1988-05-23 1990-10-02 Amoco Corporation Process for preparing polyamide-imide foam
DE19640130A1 (de) 1996-09-28 1998-04-02 Dittrich Schluessel Kg Verfahren zum Herstellen von geschäumten Formkörpern und nach dem Verfahren hergestellte Formkörper
DE19746265A1 (de) 1997-10-20 1999-04-22 Bayer Ag Verbunde aus Polyurethan und einem thermoplastischen Material
DE19860611C1 (de) 1998-12-29 2000-03-23 Fraunhofer Ges Forschung Verfahren zur Herstellung von Formkörpern aus Polymer-Schaumpartikeln
EP1155799A1 (de) 2000-05-18 2001-11-21 Jacob Formschaumtechnik GmbH, Kunststoff-Verarbeitung mit Formenbau Verfahren zur Herstellung eines aus Partikelschaum wie EPP oder EPS gebildeten Schaumkörpers in einem Formteilautomat
WO2005105404A1 (en) 2004-05-03 2005-11-10 Polma Co., Ltd. Molding method and apparatus for expandable polymer resin
DE102005039976A1 (de) 2005-08-23 2007-03-08 Basf Ag Partikel aus expandierbarem Polystyrol und daraus erhältliche Formteile mit verbessertem Brandverhalten
DE102005050411A1 (de) 2005-10-19 2007-04-26 Basf Ag Schuhsohlen auf Basis von geschäumtem thermoplastischen Polyurethan (TPU)
DE202010010411U1 (de) 2010-07-19 2011-03-10 Becker, Hendrik Wärmeisolierendes Trinkgefäß aus EPP (Expandiertem Poly-Propylen) mit und ohne Deckel
GB201115724D0 (en) 2011-09-12 2011-10-26 Origin Ltd Methods of manufacturing plastic articles
US20140343184A1 (en) 2011-12-22 2014-11-20 Solvay Specialty Polymers Usa, Llc. Thermoformed foam articles
TWI564327B (zh) * 2014-09-30 2017-01-01 積水化成品工業股份有限公司 發泡性樹脂粒子，以及顆粒發泡成形體之製造方法
US10688698B2 (en) * 2014-11-26 2020-06-23 Lifoam Industries, Llc Method of molding foam articles
DE102015017075B4 (de) * 2015-02-05 2019-06-19 Adidas Ag Verfahren zur Herstellung eines Kunststoffformteils, Kunststoffformteil und Schuh
NL2015137B1 (en) 2015-07-10 2017-02-01 Fits Holding Bv Method of manufacturing a sandwich panel having an asymmetrical configuration in thickness direction.
DE102016100690A1 (de) 2016-01-18 2017-07-20 Kurtz Gmbh Verfahren und Vorrichtung zur Herstellung eines Partikelschaumstoffteils
US20200207939A1 (en) 2017-08-24 2020-07-02 Evonik Operations Gmbh PEI particle foams for applications in aircraft interiors
WO2019101667A1 (de) 2017-11-27 2019-05-31 Evonik Röhm Gmbh Pesu-partikelschäume für anwendungen im luftfahrt-interieur
WO2019101704A1 (de) 2017-11-27 2019-05-31 Evonik Röhm Gmbh Pes-ppsu-blends als basis für schaumstoffe

Also Published As

Publication number Publication date
IL274860A (en) 2020-07-30
BR112020010391A2 (pt) 2020-10-20
DK3717211T3 (da) 2023-04-03
ZA202003629B (en) 2021-07-28
RU2020120918A (ru) 2021-12-29
WO2019101703A1 (de) 2019-05-31
MX2020005293A (es) 2020-10-07
CN111819069A (zh) 2020-10-23
AU2018373661A1 (en) 2020-07-16
JP2021504189A (ja) 2021-02-15
KR20200087258A (ko) 2020-07-20
SG11202004813YA (en) 2020-06-29
EP3717211A1 (de) 2020-10-07
BR112020010391B1 (pt) 2023-04-25
EP3717211B1 (de) 2023-01-25
CN111819069B (zh) 2023-02-21
CA3083397A1 (en) 2019-05-31
TW201936360A (zh) 2019-09-16
RU2020120918A3 (pl) 2022-04-27
KR102701369B1 (ko) 2024-08-30
US11485832B2 (en) 2022-11-01
TWI776999B (zh) 2022-09-11
ES2939295T3 (es) 2023-04-20
JP7263352B2 (ja) 2023-04-24
IL274860B1 (en) 2024-09-01
US20200325298A1 (en) 2020-10-15
AU2018373661B2 (en) 2024-02-08

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