Expandable thermoplastic composition, thermoplastic foam, and method for producing the same

Abstract

A foam article comprising a thermoplastic closed-cell foam is disclosed, which has at least a first surface and comprises (i) a thermoplastic polymer cell wall comprising at least about 0.5% by weight of an ethylene furanoate portion and optionally one or more comonomer portions, and (ii) a blowing agent comprising HFC-152a contained in at least a portion of the closed cells.

Description

[Technical Field]

[0001] The present invention relates to foamable thermoplastic compositions, thermoplastic foams, foaming methods, and systems and articles produced therefrom. [Background technology]

[0002] While foams are used in a wide variety of applications, it is desirable, but difficult, for many applications to achieve, that foam materials be environmentally friendly, possess excellent performance characteristics, and be cost-effective to produce. Environmental considerations include not only the recyclability and sustainability of the polymer resins that form the foam structure, but also the low environmental impact of the blowing agents used to form the foam, such as the global warming potential (GWP) and ozone depletion potential (ODP).

[0003] Certain thermoplastic foams, including polyester resins, have been investigated for their potential advantages in terms of recyclability and / or sustainable availability. However, challenges have been encountered in the development of such materials. For example, the challenge has been to develop polyester resins that are truly recyclable, can be produced from sustainable sources, and are compatible with blowing agents that can be combined with thermoplastic materials to produce foams with good performance characteristics. In many applications, highly desirable performance characteristics include the production of high-quality closed-cell foams that are low in density (and therefore lightweight in use) while simultaneously possessing relatively high mechanical integrity and strength.

[0004] Regarding the selection of thermoplastic resins, European Patent No. 3,231,836 expressed interest in thermoplastic resins, particularly polyester resins, but acknowledged that this interest faced development challenges, including the difficulty in identifying suitable foaming grades of such resins. Furthermore, European Patent No. 3,231,836 mentions that certain polyethylene terephthalate (PET) resins (including recycled versions of PET) can be melt-extruded with suitable physical and / or chemical blowing agents to obtain closed-cell foams with the potential for low density and good mechanical properties, but it does not disclose that any of such resins can immediately produce foams with good environmental and performance properties, and can also be formed from sustainable sources. Application No. 836 identifies several candidate polyester resins for use in forming open-cell foams, comprising polyethylene terephthalate, polybutylene terephthalate, polycyclohexane terephthalate, polyethylene naphthalate, polyethylene furanoate, or mixtures of two or more of these. While the use of polyester materials to produce foams that essentially lack closed cells, as required by European Patent No. 836, may be beneficial for some applications, a drawback of such structures is that open-cell foams generally exhibit relatively poor mechanical strength properties.

[0005] Chinese Patent No. 108484959 discloses that the production of foam products based on 2,5-flangemethyl copolyester is problematic because the dissolution of foaming agents into polyester is alleged to be an issue, and proposes a specific process including the use of a combination of liquid and gaseous foaming agents, and the sequential use of these different classes of foaming agents.

[0006] U.S. Publication Nos. 2020 / 0308363 and 2020 / 0308396 disclose the production of amorphous polyester copolymers, which include starting from recycled polyester, with PET as the primary component, and then obtaining amorphous copolymers, i.e., copolymers that do not have crystalline properties, through a series of processing steps. A wide variety of different classes of blowing agents for use with such amorphous polymers are mentioned.

[0007] U.S. Publication Nos. 2020 / 0308363 and 2020 / 0308396 disclose the production of amorphous polyester copolymers, which include starting from recycled polyester, with PET as the primary component, and then obtaining amorphous copolymers, i.e., copolymers that do not have crystalline properties, through a series of processing steps. A wide variety of different classes of blowing agents for use with such amorphous polymers are mentioned.

[0008] The applicants have come to recognize that by using the polyester resins disclosed herein in combination with blowing agents comprising one or more hydrohaloolefins disclosed herein, one or more unexpected advantages can be achieved in relation to the formation of thermoplastic foams, particularly extruded thermoplastic foams. [Overview of the project]

[0009] The present invention (a) A thermoplastic polymer bubble having a cell wall that forms a closed cell, wherein the ethylene furanoate portion is at least 1 mol% of the thermoplastic polymer, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1A.

[0010] The present invention also, (a) A closed thermoplastic cell comprising a cell wall that forms a closed cell, wherein the cell wall is treated with a chain extender and essentially consists of polyethylene furanoate having a molecular weight greater than 25,000, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1B.

[0011] The present invention (a) A closed thermoplastic cell comprising a cell wall containing polyethylene furanoate having a molecular weight greater than 25,000, wherein the ethylene furanoate portion constitutes at least 70% by weight of the thermoplastic polymer, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1C.

[0012] The present invention (a) A closed thermoplastic cell comprising a cell wall containing polyethylene furanoate having a molecular weight greater than 25,000, wherein the ethylene furanoate portion, which is at least 90% of the thermoplastic material, contains an ethylene furanoate portion, and (b) A low-density closed-cell thermoplastic foam containing 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1D.

[0013] The present invention (a) Thermoplastic polymer bubbles including a cell wall, wherein at least about 50% by volume of the bubbles are closed cells, and the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1E.

[0014] The present invention (a) Thermoplastic polymer bubbles comprising cell walls containing polyethylene furanoate having a molecular weight greater than 25,000, wherein the ethylene furanoate portion constitutes at least 50% of the thermoplastic material, and at least about 50% by volume of the bubbles are closed cells, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1F.

[0015] The present invention (a) Thermoplastic polymer bubbles comprising cell walls containing polyethylene furanoate having a molecular weight greater than 25,000, wherein the ethylene furanoate portion constitutes at least 50% of the thermoplastic material, and at least about 75% by volume of the bubbles are closed cells, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1G.

[0016] The present invention (a) Thermoplastic polymer bubbles comprising cell walls containing polyethylene furanoate having a molecular weight greater than 25,000, wherein the ethylene furanoate portion constitutes at least 50% of the thermoplastic material, and at least about 90% by volume of the bubbles are closed cells, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For the sake of convenience, in this specification, the foam according to this paragraph is referred to as Foam 1H.

[0017] The present invention is (a) a thermoplastic polymer foam comprising cell walls containing polyethylene furanoate treated with a chain extender and having a molecular weight of more than 50,000, wherein the ethylene furanoate moiety is at least 50% of the thermoplastic material and at least about 50% by volume of the cells are closed cells, and (b) 1,1-difluoroethane (HFC-152a) contained within the closed cells, and comprises a low density thermoplastic foam. For the sake of convenience, in this specification, the foam according to this paragraph is referred to as Foam 1I.

[0018] The present invention is (a) a thermoplastic polymer foam comprising cell walls containing polyethylene furanoate treated with a chain extender and having a molecular weight of more than 50,000, wherein the ethylene furanoate moiety is at least 50% of the thermoplastic material and at least about 75% by volume of the cells are closed cells, and (b) 1,1-difluoroethane (HFC-152a) contained within the closed cells, and comprises a low density thermoplastic foam. For the sake of convenience, in this specification, the foam according to this paragraph is referred to as Foam 1J.

[0019] The present invention is (a) a thermoplastic polymer foam comprising cell walls containing polyethylene furanoate treated with a chain extender and having a molecular weight of more than 50,000, wherein the ethylene furanoate moiety is at least 50% of the thermoplastic material and at least about 90% by volume of the cells are closed cells, and (b) 1,1-difluoroethane (HFC-152a) contained within the closed cells, and comprises a low density thermoplastic foam. For the sake of convenience, in this specification, the foam according to this paragraph is referred to as Foam 1K.

[0020] The present invention is (a) Thermoplastic polymer bubbles comprising cell walls containing polyethylene furanoate treated with a chain extender and having a molecular weight of at least about 90,000, wherein the ethylene furanoate portion constitutes at least 50% of the thermoplastic material, and at least about 50% by volume of the bubbles are closed cells, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam prepared in this paragraph will be referred to as 1 liter of foam in this specification.

[0021] The present invention (a) Thermoplastic polymer bubbles comprising cell walls containing polyethylene furanoate treated with a chain extender and having a molecular weight of at least about 90,000, wherein the ethylene furanoate portion constitutes at least 50% of the thermoplastic material, and at least about 75% by volume of the bubbles are closed cells, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1M.

[0022] The present invention (a) Thermoplastic polymer bubbles comprising a cell wall containing polyethylene furanoate treated with a chain extender and having a molecular weight of at least about 90,000, wherein the ethylene furanoate portion constitutes at least 50% of the thermoplastic material, and at least about 90% by volume of the bubbles are closed cells, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 1N.

[0023] The present invention (a) Closed thermoplastic cells containing cell walls essentially made of polyethylene furanoate, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained within the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a density of less than 0.3 g / cc. For convenience, the foam according to this paragraph shall be referred to as foam 2A in this specification.

[0024] The present invention (a) Closed thermoplastic cells containing cell walls essentially made of polyethylene furanoate, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained within the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a density of less than 0.25 g / cc. For convenience, the foam according to this paragraph shall be referred to as foam 2B in this specification.

[0025] The present invention (a) Thermoplastic polymer bubbles comprising a cell wall containing polyethylene furanoate, wherein at least about 50 volume percent of the bubbles are closed cells, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foaming density (RFD) of about 0.2 or less. For convenience, the foam according to this paragraph shall be referred to as foam 2C in this specification.

[0026] The present invention (a) a thermoplastic bubble including a cell wall, wherein (1) the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender, and (iii) at least about 50% by volume of the bubble is a closed cell, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foaming density (RFD) of about 0.2 or less. For convenience, the foam according to this paragraph shall be referred to as foam 2D ​​in this specification.

[0027] The present invention (a) Thermoplastic bubbles including a cell wall, (1) the ethylene furanoate portion is at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight greater than 25,000, and (iii) at least about 50% by volume of the bubbles are closed cells, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, (ii) The foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2 or less. For convenience, the foam according to this paragraph will be referred to as foam 2E in this specification.

[0028] The present invention (a) Thermoplastic bubbles including a cell wall, (1) the ethylene furanoate portion is at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight greater than 50,000, and (iii) at least about 50% by volume of the bubbles are closed cells, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2. For convenience, the foam according to this paragraph shall be referred to as foam 2F in this specification.

[0029] The present invention (a) A thermoplastic bubble containing a cell wall, wherein (1) the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight of at least about 90,000, and (iii) at least about 50% by volume of the bubble is a closed cell, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2. For convenience, the foam according to this paragraph shall be referred to as foam 2G.

[0030] The present invention (a) A thermoplastic bubble containing a cell wall, wherein (1) the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight greater than 25,000, and (iii) at least about 75% by volume of the bubble is a closed cell, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2. For convenience, the foam according to this paragraph shall be referred to as foam 2H.

[0031] The present invention (a) A thermoplastic bubble containing a cell wall, wherein (1) the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight greater than 50,000, and (iii) at least about 75% by volume of the bubble is a closed cell, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2. For convenience, the foam according to this paragraph shall be referred to as foam 2I.

[0032] The present invention (a) A thermoplastic bubble containing a cell wall, wherein (1) the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight of at least about 90,000, and (iii) at least about 75% by volume of the bubble is a closed cell, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2. For convenience, the foam according to this paragraph shall be referred to as foam 2J in this specification.

[0033] The present invention (a) A thermoplastic bubble containing a cell wall, wherein (1) the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight greater than 25,000, and (iii) at least about 90% by volume of the bubble is a closed cell, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2. For convenience, the foam according to this paragraph shall be referred to as foam 2K in this specification.

[0034] The present invention (a) A thermoplastic bubble containing a cell wall, wherein (1) the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight greater than 50,000, and (iii) at least about 90% by volume of the bubble is a closed cell, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2. For convenience, the foam according to this paragraph shall be referred to as foam 2L in this specification.

[0035] The present invention (a) A thermoplastic bubble containing a cell wall, wherein (1) the ethylene furanoate portion constitutes at least 50% by weight of the thermoplastic polymer forming the cell wall, (ii) the thermoplastic polymer is treated with a chain extender and has a molecular weight of at least about 90,000, and (iii) at least about 90% by volume of the bubble is a closed cell, (b) A low-density closed-cell thermoplastic foam comprising a 1,1-difluoroethane (HFC-152a) blowing agent contained in the closed cells, wherein the foam comprises a low-density closed-cell thermoplastic foam having a relative foam density (RFD) of about 0.2. For convenience, the foam according to this paragraph shall be referred to as foam 2M.

[0036] The present invention (a) Thermoplastic polymer bubbles comprising cell walls forming closed cells, wherein the thermoplastic polymer has a degree of crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an optional ethylene terephthalate moiety, wherein the polymer comprises about 1 mol% to about 100 mol% of the ethylene furanoate moiety and optionally at least about 1 mol% of the ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3A.

[0037] The present invention (a) Thermoplastic polymer bubbles comprising cell walls forming closed cells, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 1 mol% to about 20 mol% of the ethylene furanoate moiety and at least about 1 mol% of the ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3B.

[0038] The present invention (a) Thermoplastic polymer bubbles comprising cell walls forming closed cells, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a degree of crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 1 mol% to about 20 mol% of the ethylene furanoate moiety and about 80 mol% to about 99 mol% of the ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3C.

[0039] The present invention (a) Thermoplastic polymer bubbles comprising cell walls forming closed cells, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a degree of crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 1 mol% to about 10 mol% of the ethylene furanoate moiety and about 90 mol% to about 99 mol% of the ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3D.

[0040] The present invention (a) Thermoplastic polymer bubbles comprising cell walls forming closed cells, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a degree of crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 1 mol% to about 5 mol% of the ethylene furanoate moiety and about 95 mol% to about 99 mol% of the ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3E.

[0041] The present invention (a) Thermoplastic polymer bubbles comprising cell walls forming closed cells, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 0.5 mol% to about 2 mol% of the ethylene furanoate moiety and about 98 mol% to about 99.5 mol% of the ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3F.

[0042] The present invention (a) A thermoplastic polymer bubble comprising a cell wall forming a closed cell, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a degree of crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 1 mol% of an ethylene furanoate moiety and about 99 mol% of an ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3G.

[0043] The present invention (a) A thermoplastic polymer bubble comprising a cell wall forming a closed cell, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 0.5 mol% of an ethylene furanoate moiety and about 99.5 mol% of an ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3H.

[0044] The present invention (a) A thermoplastic polymer bubble comprising a cell wall forming a closed cell, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a degree of crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 5 mol% of an ethylene furanoate moiety and about 95 mol% of an ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3I.

[0045] The present invention (a) A thermoplastic polymer bubble comprising a cell wall forming a closed cell, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a degree of crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 10 mol% of an ethylene furanoate moiety and about 90 mol% of an ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3J.

[0046] The present invention (a) A thermoplastic polymer bubble comprising a cell wall forming a closed cell, wherein the thermoplastic polymer has a molecular weight of at least about 10,000 kg / mol and a degree of crystallinity of at least about 5%, and is essentially composed of an ethylene furanoate moiety and an ethylene terephthalate moiety, wherein the polymer comprises about 20 mol% of an ethylene furanoate moiety and about 80 mol% of an ethylene terephthalate moiety, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3K.

[0047] The present invention (a) Thermoplastic polymer bubbles comprising a cell wall containing polyethylene furanoate, wherein at least 25% of the bubbles are closed cells, (b) A low-density thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in closed cells. For convenience, the foam described in this paragraph will be referred to as foam 3L.

[0048] The present invention (a) Closed thermoplastic cells containing cell walls essentially made of polyethylene furanoate, (b) A low-density closed-cell thermoplastic foam containing 1,1-difluoroethane (HFC-152a) contained in the closed cells, The foam comprises a low-density closed-cell thermoplastic foam having a density of less than 0.3 g / cc. For convenience, the foam described in this paragraph will be referred to as foam 4A.

[0049] The present invention (a) Closed thermoplastic cells containing cell walls essentially made of polyethylene furanoate, (b) A low-density closed-cell thermoplastic foam containing 1,1-difluoroethane (HFC-152a) contained in the closed cells, The foam comprises a low-density closed-cell thermoplastic foam having a density of less than 0.2 g / cc. For convenience, the foam described in this paragraph will be referred to as foam 4B.

[0050] The present invention (a) Closed thermoplastic cells containing cell walls essentially made of polyethylene furanoate, (b) A low-density closed-cell thermoplastic foam containing 1,1-difluoroethane (HFC-152a) contained in the closed cells, The foam comprises a low-density closed-cell thermoplastic foam having a density of 0.1 g / cc or less. For convenience, the foam described in this paragraph will be referred to as foam 4C.

[0051] The present invention (a) Closed thermoplastic cells comprising cell walls essentially made of polyethylene furanoate, wherein at least about 50 volume percent of the cells are closed cells, (b) A low-density closed-cell thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in the closed cells. For convenience, the foam according to this paragraph will be referred to as foam 4D.

[0052] The present invention (a) Closed thermoplastic cells comprising cell walls essentially made of polyethylene furanoate, wherein at least about 75% by volume of the cells are closed cells, (b) A low-density closed-cell thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in the closed cells. For convenience, the foam according to this paragraph will be referred to as foam 4E.

[0053] The present invention (a) Closed thermoplastic cells comprising cell walls essentially made of polyethylene furanoate, wherein at least about 90% by volume of the cells are closed cells, (b) A low-density closed-cell thermoplastic foam comprising 1,1-difluoroethane (HFC-152a) contained in the closed cells. For convenience, the foam according to this paragraph will be referred to as foam 4F.

[0054] The present invention (a) A thermoplastic material essentially consisting of polyethylene furanoate having a molecular weight greater than 25,000, wherein at least 50% of the thermoplastic material contains an ethylene furanoate moiety, (b) A foaming thermoplastic composition comprising 1,1-difluoroethane (HFC-152a). For convenience, the foaming composition according to this paragraph will be referred to as foaming composition 1A.

[0055] The present invention (a) A thermoplastic material essentially consisting of polyethylene furanoate having a molecular weight greater than 100,000, wherein at least 50% of the thermoplastic material contains an ethylene furanoate portion, (b) A foaming thermoplastic composition comprising 1,1-difluoroethane (HFC-152a). For convenience, the foaming composition according to this paragraph will be referred to as foaming composition 1B.

[0056] The present invention (a) A thermoplastic material essentially consisting of chain-extended polyethylene furanoate having a molecular weight greater than 100,000, wherein at least 90% of the thermoplastic material contains an ethylene furanoate moiety, (b) A foaming thermoplastic composition comprising 1,1-difluoroethane (HFC-152a). For convenience, the foaming composition according to this paragraph will be referred to as foaming composition 1C.

[0057] The present invention also provides a method for forming a thermoplastic foam, comprising foaming a foaming composition of the present invention, each comprising foaming compositions 1A to 1C. For convenience, the method according to this paragraph will be referred to as foaming method 1.

[0058] The present invention also provides a method for forming an extruded thermoplastic foam, comprising extruding the foamed compositions of the present invention, each comprising foamed compositions 1A to 1C. For convenience, the method according to this paragraph will be referred to as foaming method 2. [Brief explanation of the drawing]

[0059] [Figure 1] This is a schematic diagram of an embodiment of the present invention and an extrusion system and process according to the embodiments herein. [Figure 2] This is a cross-sectional view of an exemplary coated foam of the present invention in a specific form of sandwich structure. [Figure 3] This is a schematic diagram of an example wind turbine. [Figure 4] This is a semi-circular diagram of an exemplary wind turbine. [Figure 5A] This is an illustrative cross-sectional view of a wind turbine blade. [Figure 5B] This is an illustrative cross-sectional view of a wind turbine blade. [Figure 5C] This is an illustrative cross-sectional view of a wind turbine blade. [Modes for carrying out the invention]

[0060] definition HFC-152a stands for 1,1-difluoroethane. 1234ze means 1,1,1,3-tetrafluoropropene and is not limited to isomer morphology. Trans-1234ze and 1234ze(E) refer to trans-1,3,3,3-tetrafluoropropene, respectively. cis1234ze and 1234ze(Z) each refer to cis-1,3,3,3-tetrafluoropropene. 1234yf stands for 2,3,3,3-tetrafluoropropene. 1233zd means 1-chloro-3,3,3-trifluoropropene and is not limited to isomer morphology. Trans-1233zd and 1233zd(E) refer to trans-1-chloro-3,3,3-trifluoropropene, respectively. 1224yd means cis-1-chloro-2,3,3,3-tetrafluoropropane and is not limited to isomer morphology. 1336mzz refers to 1,1,1,4,4,4-hexafluorobutene and is not limited to isomer morphology. Trans-1336mzz and 1336mzz(E) refer to trans-1,1,1,4,4,4-hexafluorobutene, respectively. cis1336mzz and 1336mzz(Z) refer to cis1,1,1,4,4,4-hexafluorobutene, respectively. A closed-cell foam means that a substantial volume percentage of the bubbles in the foam, for example, about 20% or more by volume, are independent cells.

[0061] The ethylene furanoate portion has the following structure:

[0062] [ka]

[0063] FDCA stands for 2,5-franzicarboxylic acid and has the following structure.

[0064] [ka]

[0065] MEG stands for monoethylene glycol and has the following structure.

[0066] [ka]

[0067] FDME stands for 2,5-dimethyl francylcarboxylate and has the following structure.

[0068] [ka]

[0069] PEF homopolymer refers to a polymer having at least 99 mol% ethylene furanoate moiety.

[0070] PEF copolymer refers to a polymer having at least about 1 mol% of ethylene furanoate and more than 1% of polymer parts other than ethylene furanoate.

[0071] PEF:PET copolymer refers to a polymer having at least about 1 mol% of an ethylene furanoate moiety and at least 1% of an ethylene terephthalate moiety.

[0072] PEF stands for poly(ethylene furanoate) and is intended to encompass and reflect the descriptions of PEF homopolymer and PEF copolymer.

[0073] The ethylene terephthalate portion has the following structure:

[0074] [ka]

[0075] SSP stands for solid-phase polymerization.

[0076] PMDA refers to pyromellitic dianhydride having the following structure.

[0077] [ka]

[0078] PMDA refers to pyromellitic dianhydride having the following structure.

[0079] [ka] (Modes for carrying out the invention)

[0080] Poly(ethylene furanoate) The present invention relates to a foam and a foam article containing a cellular wall formed of PEF.

[0081] The PEF that forms the bubble walls of the foam and foam article of the present invention may be a PEF homopolymer or a PEF copolymer, particularly a PEF:PET copolymer.

[0082] PEF homopolymers are known materials that are formed by either (a) esterification and polycondensation of FDCA and MEG, or (b) transesterification and polycondensation of FDME and MEG, as illustrated below, for example.

[0083] [ka]

[0084] A detailed description of such known esterification and polycondensation synthesis methods is provided in British Patent No. 621971 (Drewitt, JGN and Lincoln, J., titled "Improvements in Polymers"), which is incorporated herein by reference. A detailed description of such known transesterification and polycondensation synthesis methods is provided in Gandini, A., Silvestre, AJD, Neto, CP, Sousa, AF, and Gomes, M. (2009), "The furan counterpart of poly(ethylene terephthalate): an alternative material based on renewable resources," J.Polym.Sci.Polym.Chem. 47, 295-298. doi:10.1002 / pola.23130, which is incorporated herein by reference.

[0085] foam The foam of the present invention is formed from either a PEF homopolymer, a PEF copolymer, or a combination / mixture thereof.

[0086] The foam of the present invention, comprising each of foams 1 to 4, is formed from either a PEF homopolymer, a PEF copolymer, or a combination / mixture thereof.

[0087] In preferred embodiments, the foams of the present invention, each comprising foams 1 to 4, may be formed from a PEF homopolymer having at least 99.5% by weight or at least 99.9% by weight of an ethylene furanoate moiety.

[0088] In preferred embodiments, the foams of the present invention, each of foams 1 to 4, are intended to be formed from a PEF copolymer having a polymer comprising about 60% to about 99% by weight of ethylene furanoate, or about 70% to about 99% by weight of ethylene furanoate, or about 80% to about 99% by weight of ethylene furanoate, or about 90% to about 99% by weight of ethylene furanoate, or about 95% to about 99.5% by weight of ethylene furanoate.

[0089] In preferred embodiments, the foams of the present invention, each of foams 1 to 4, are intended to be formed from a PEF copolymer having a polymer comprising about 40% to about 1% by weight of ethylene furanoate, or about 30% to about 1% by weight of ethylene furanoate, or about 20% to about 1% by weight of ethylene furanoate, or about 10% to about 1% by weight of ethylene furanoate, or about 5% to about 1% by weight of ethylene furanoate, or about 5% to about 0.5% by weight of ethylene furanoate.

[0090] In preferred embodiments, the foams of the present invention, each of foams 1 to 4, are intended to be formed from a PEF copolymer having a polymer comprising about 40 mol% to about 1 mol% of ethylene furanoate moiety, or about 30 mol% to about 1 mol% of ethylene furanoate moiety, or about 20 mol% to about 1 mol% of ethylene furanoate moiety, or about 10 mol% to about 1 mol% of ethylene furanoate moiety, or about 5 mol% to about 1 mol% of ethylene furanoate moiety, or about 5 mol% to about 0.5 mol% of ethylene furanoate moiety.

[0091] In a preferred embodiment, the foam of the present invention, comprising each of foams 1 to 4, contains a polymer comprising about 40 mol% to about 1 mol% ethylene furanoate and about 60 mol% to about 99 mol% ethylene terephthalate, or about 30 mol% to about 1 mol% ethylene furanoate and about 70 mol% to about 99 mol% ethylene terephthalate, or about 20 mol% to about 1 mol% ethylene furanoate and about 80 mol% to about 99 mol% ethylene terephthalate. It is intended to be formed from a PEF copolymer having a phthalate portion, or an ethylene furanoate portion of about 10 mol% to about 1 mol% and an ethylene terephthalate portion of about 90 mol% to about 99 mol%, or an ethylene furanoate portion of about 5 mol% to about 1 mol% and an ethylene terephthalate portion of about 95 mol% to about 99 mol%, or an ethylene furanoate portion of about 5 mol% to about 0.5 mol% and an ethylene terephthalate portion of about 95 mol% to about 99.5 mol%.

[0092] With respect to these embodiments of the present invention, including PEF copolymers, it is intended that those skilled in the art, taking into account the teachings contained herein, can select the type and amount of copolymer material to be used within each of the ranges described herein in order to achieve the desired enhancement / modification of the polymer without excessive experimentation.

[0093] With respect to these embodiments of the present invention involving the use of PEF homopolymers or PEF copolymers, it is intended that such materials having a wide variety of molecular weights and physical properties within the scope of the present invention can be formed. In preferred embodiments, foams comprising each of foams 1 to 4 are formed from PEF having the range of properties specified in Table 1 below, as measured as described in the examples herein.

[0094] [Table 1]

[0095] Generally, it is intended that those skilled in the art can formulate PEF polymers within the range of the above properties without excessive experimentation, taking into account the teachings contained herein. However, in preferred embodiments, PEF (including PEF homopolymers and PEF copolymers) having these properties is achieved by using one or more of the above synthesis methods in combination with various known supplemental processing techniques, including treatment with chain extenders such as PMDA (and PMDA substitutes and supplements such as ADR, PENTA, and talc, as described in the Examples of the Invention and elsewhere) and / or SSP treatment. Taking into account the disclosures contained herein, including the polymer synthesis described in the following Examples and the use of methods to enhance polymer crystallization, it is considered that those skilled in the art can produce PEF polymers within the range of properties described in the above Table and elsewhere in this Spec. Such processing conditions include methods to increase crystallization described herein, including thermoplastic formation method 1 of the Invention, such methods are those disclosed in the Examples of this Spec.

[0096] An example of a process for chain extension treatment of polyester is provided in the literature “Recycled poly(ethylene terephthalate) chain extension by a reactive extrusion process,” Firas Awaja, Fugen Daver, Edward Kosior, 16 August 2004, https: / / doi.org / 10.1002 / pen.20155, which is incorporated herein by reference. As described in U.S. Publication No. 1009 / 0264545, incorporated herein by reference, chain extenders are generally compounds that are at least bifunctional with respect to reactive groups that can react with terminal groups or functional groups in polyester to extend the length of polymer chains. In particular cases, as disclosed herein, such treatments can favorably increase the average molecular weight of the polyester and improve its melt strength and / or other important properties. The degree of chain extension achieved is at least in part related to the structure and functionality of the compound used. A variety of compounds are useful as chain extenders. Non-limiting examples of chain extenders include trimellitic anhydride, pyromellitic dianhydride (PMDA), trimellitic acid, its haloformyl derivatives, or compounds containing polyfunctional epoxy (e.g., glycidyl) or oxazoline functional groups. Nanocomposite materials, such as finely dispersed nanoclay, may optionally be used to control viscosity. Commercially available chain extenders include Clariant's CESA-Extend, BASF's Joncryl, or Arkema's Lotader. The amount of chain extender may vary depending on the type and molecular weight of the polyester component. The amount of chain extender used to process the polymer can vary widely, in preferred embodiments ranging from about 0.1 to about 5% by weight, or preferably from about 0.1 to about 1.5% by weight. Examples of chain extenders are also described in U.S. Patent No. 4,219,527, which is incorporated herein by reference.

[0097] An example of a process for SSP treatment of poly(ethylene furanoate) is found in the paper "Solid-State Polymerization of Poly(ethylene furanoate) Biobased Polyester, I: Effect of Catalyst Type on Molecular Weight Increase." Provided to Nejib Kasmi, Mustapha Majdoub, George Z. Papageorgiou, Dimitris S. Achilias, and Dimitrios N. Bikiaris, which are incorporated herein by reference.

[0098] PEF thermoplastic polymers particularly advantageous for producing the foaming compositions and foams of the present invention are identified in the following thermoplastic polymer table (Table 2A), and all numerical values ​​in the table are understood to be preceded by the word "approximately".

[0099] [Table 2]

[0100] The PEF thermoplastic polymers particularly advantageous for producing the foaming compositions and foams of the present invention also include the materials specified in the following thermoplastic polymer table (Table 2B), and all numerical values ​​in the table are understood to be preceded by the word "approximately".

[0101] [Table 3]

[0102] The PEF thermoplastic polymers particularly advantageous for producing the foaming compositions and foams of the present invention also include the materials specified in the following thermoplastic polymer table (Table 2C), and all numerical values ​​in the table are understood to be preceded by the word "approximately".

[0103] [Table 4-1]

[0104] [Table 4-2]

[0105] For the purposes of defining terms used herein, note that in various parts of this specification, thermoplastic polymers identified in the first column of each row in the TPP table above are referenced, and each reference to one of these numbers is a reference to the thermoplastic polymer defined in the corresponding column of that row. References to the group of TPPs defined in the table above by reference to the TPP number mean each such numbered TPP, including any such number with a subscript, and each TPP having the indicated number, separately and individually. For example, a reference to TPP1 is a separate and independent reference to TPP1A, TPP1B, TPP1C, TPP1D, and TPP1E. References to TPP1-TPP2 are separate and independent references to TPP1A, TPP1B, TPP1C, TPP1D, TPP1E, TPP2A, TPP2B, TPP2C, TPP2D, and TPP1E. This convention of use is also applied to the following tables of foamed compositions and foams.

[0106] foaming agent As described in detail herein, the present invention includes the applicant's discovery that HFC-152a as a blowing agent in the foaming composition, foam and method of the present invention can provide foaming PEF composition and PEF foam that are difficult to achieve in terms of achieving a remarkable combination of physical properties, including low density and good mechanical strength properties.

[0107] Therefore, the blowing agent used in accordance with the present invention preferably contains HFC-152a. For convenience, the blowing agent according to this paragraph may be referred to as blowing agent 1A in this specification.

[0108] Therefore, the blowing agent used in accordance with the present invention preferably contains at least about 50% by weight of HFC-152a. For convenience, the blowing agent according to this paragraph may be referred to as blowing agent 1B in this specification.

[0109] Therefore, the blowing agent used in accordance with the present invention preferably contains at least about 60% by weight of HFC-152a. For convenience, the blowing agent according to this paragraph may be referred to as blowing agent 1C in this specification.

[0110] Therefore, the blowing agent used in accordance with the present invention preferably contains at least about 70% by weight of HFC-152a. For convenience, the blowing agent according to this paragraph may be referred to as blowing agent 1D in this specification.

[0111] Therefore, the blowing agent used in accordance with the present invention preferably contains at least about 80% by weight of HFC-152a. For convenience, the blowing agent according to this paragraph may be referred to as blowing agent 1E in this specification.

[0112] Therefore, the blowing agent used in accordance with the present invention preferably contains at least about 90% by weight of HFC-152a. For convenience, the blowing agent according to this paragraph may be referred to as blowing agent 1F in this specification.

[0113] Therefore, the blowing agent used in accordance with the present invention preferably contains at least about 95% by weight of HFC-152a. For convenience, the blowing agent according to this paragraph may be referred to as blowing agent 1G in this specification.

[0114] Therefore, the blowing agent used in accordance with the present invention preferably consists essentially of HFC-152a. For convenience, the blowing agent according to this paragraph may be referred to as blowing agent 1H in this specification.

[0115] The foaming agent used in accordance with the present invention preferably consists of HFC-152a. For convenience, the foaming agent according to this paragraph may be referred to as foaming agent 1I in this specification.

[0116] The preferred blowing agents of the present invention also preferably comprise HFC-152a and one or more of 1234ze, 1234yf, 1336mzz, 1233zd, and 1224ydf (hereinafter referred to as blowing agent 2 for convenience), or HFC-152a and one or more of trans 1234ze, 1336mzz, trans 1233zd, and cis 1224yd (hereinafter referred to as blowing agent 3 for convenience), or HFC-152a and one or more of trans 1234ze, trans 1336mzz, trans 1233zd, and cis 1224yd (hereinafter referred to as blowing agent 4 for convenience), or HFC-152a and trans 1234ze and trans 1336mzz It contains one or more of z (hereinafter referred to as foaming agent 5 for convenience), or HFC-152a and trans 1234ze (hereinafter referred to as foaming agent 6 for convenience), or HFC-152a and trans 1336mzz (hereinafter referred to as foaming agent 7 for convenience), or HFC-152a and cis 1336mzz (hereinafter referred to as foaming agent 8 for convenience), or HFC-152a and 1234yf (hereinafter referred to as foaming agent 9 for convenience), or HFC-152a and 1224yd (hereinafter referred to as foaming agent 10 for convenience), or HFC-152a and trans 1233zd (hereinafter referred to as foaming agent 11 for convenience). Accordingly, the blowing agents of the present invention, each comprising blowing agents 1 to 11, are intended to include additional co-blowing agents comprising one or more of the optional potential co-blowing agents described below, in addition to each of the blowing agents specified above. In preferred embodiments, the blowing compositions, foams, and blowing methods of the present invention comprise the blowing agents described in accordance with the selection in the paragraph, wherein the indicated blowing agents (including the compounds or groups of compounds specifically identified in each of blowing agents 1 to 11) are present in an amount of at least about 50% by weight, preferably at least about 60% by weight, preferably at least about 70% by weight, preferably at least about 80% by weight, preferably at least about 90% by weight, preferably at least about 95% by weight, or preferably at least about 99% by weight, based on the total weight of all blowing agents present.

[0117] The blowing agent used in accordance with the present invention is also preferably essentially composed of HFC-152a and one or more of 1234ze, 1234yf, 1336mzz, 1233zd and 1224ydf (hereinafter referred to as blowing agent 12 for convenience), or essentially composed of HFC-152a and one or more of trans 1234ze, 1336mzz, trans 1233zd and cis 1224yd (hereinafter referred to as blowing agent 13 for convenience), or essentially composed of HFC-152a and one or more of trans 1234ze, trans 1336mzz, trans 1233zd and cis 1224yd (hereinafter referred to as blowing agent 14 for convenience), or HFC-152a and one or more of trans 1234ze and trans 1336mzz Essentially consisting of (hereinafter referred to as blowing agent 15 for convenience), or essentially consisting of HFC-152a and transform 1234ze (hereinafter referred to as blowing agent 16 for convenience), or essentially consisting of HFC-152a and transform 1336mzz (hereinafter referred to as blowing agent 17 for convenience), or essentially consisting of HFC-152a and cis 1336mzz (Hereinafter referred to as blowing agent 18 for convenience), or essentially consisting of HFC-152a and 1234yf (hereinafter referred to as blowing agent 19 for convenience), or essentially consisting of HFC-152a and 1224yd (hereinafter referred to as blowing agent 20 for convenience), or essentially consisting of HFC-152a and trans 1233zd (hereinafter referred to as blowing agent 21 for convenience). The blowing agents of this paragraph may include one or more co-blowing agents not included in the selection shown, however, it is intended and understood that the amount of such co-blowing agents used will not interfere with or impair the ability to achieve relatively low-density foams as described herein, and preferably further, will not interfere with or impair the ability to achieve mechanical strength properties as described herein.Therefore, in consideration of the teachings contained herein, it is intended that, for example, a person skilled in the art can select, without excessive experimentation, one or more saturated hydrocarbons or hydrofluorocarbons (HFCs) known in the art, particularly one or more co-blown agents that may be C4-C6 hydrocarbons or C1-C4 HFCs, for use in a particular application. Examples of such HFC co-blown agents include, but are not limited to, difluoromethane (HFC-32), fluoroethane (HFC-161), difluoroethane (HFC-152), trifluoroethane (HFC-143), tetrafluoroethane (HFC-134), pentafluoroethane (HFC-125), pentafluoropropane (HFC-245), hexafluoropropane (HFC-236), heptafluoropropane (HFC-227ea), pentafluorobutane (HFC-365), hexafluorobutane (HFC-356), and one or a combination of all isomers of all such HFCs. With respect to hydrocarbons, the blowing agent compositions of the present invention may also, in certain preferred embodiments, include, for example, iso, n, and / or cyclopentane in thermosetting foams, and butane or isobutane in thermoplastic foams. Other materials may include, for example, water, CO2, CFCs (e.g., trichlorofluoromethane (CFC-11) and dichlorodifluoromethane (CFC-12)), hydrochlorocarbons (HCCs, for example, dichloroethylene (preferably trans-dichloroethylene), ethyl chloride and chloropropane), HCFCs, C1-C5 alcohols (e.g., ethanol and / or propanol and / or butanol), C1-C4 aldehydes, C1-C4 ketones, C1-C4 ethers (including ethers (e.g., dimethyl ether and diethyl ether), diethers (e.g., dimethoxymethane and diethoxymethane)), and methyl formate, organic acids (e.g., formic acid, but not limited to these) (including any combination thereof), but such components are not necessarily preferred in many embodiments due to their adverse environmental impact.

[0118] The blowing agent used in accordance with the present invention is also preferably composed of HFC-152a and one or more of 1234ze, 1234yf, 1336mzz, 1233zd and 1224ydf (hereinafter referred to as blowing agent 22 for convenience), or composed of HFC-152a and one or more of trans 1234ze, trans 1336mzz, trans 1233zd and cis 1224yd (hereinafter referred to as blowing agent 23 for convenience), or composed of HFC-152a and one or more of trans 1234ze, trans 1336mzz, trans 1233zd and cis 1224yd (hereinafter referred to as blowing agent 24 for convenience), or composed of HFC-152a and trans 1234ze and trans It consists of one or more of S1336mzz (hereinafter referred to as foaming agent 25 for convenience), or HFC-152a and trans1234ze (hereinafter referred to as foaming agent 26 for convenience), or HFC-152a and trans1336mzz (hereinafter referred to as foaming agent 27 for convenience), or HFC-152a and cis1336mzz (hereinafter referred to as foaming agent 28 for convenience), or HFC-152a and 1234yf (hereinafter referred to as foaming agent 29 for convenience), or 1224yd (hereinafter referred to as foaming agent 30 for convenience), or HFC-152a and trans1233zd (hereinafter referred to as foaming agent 31 for convenience).

[0119] Foams and foaming processes Any of the foams of the present invention, comprising each of foams 1 to 4, or foams made from the PEF polymers of the present invention comprising thermoplastic polymers TPP1A to TPP22E, or foams described in Examples 1 to 22, can generally be formed from the foaming compositions of the present invention. Generally, the foaming compositions of the present invention can be formed by combining the PEF polymers of the present invention, comprising each of the thermoplastic polymers TPP1A to TPP22E, with the foaming agents of the present invention, comprising each of the foaming agents 1 to 31.

[0120] Foaming compositions that fall within the scope of the present invention and offer particular advantages in relation to the formation of foams of the present invention are listed in the following tables of foaming compositions (Tables 3A and 3B), all of which are understood to be preceded by the word "approximately", and the following terms used in the tables have the following meanings.

[0121] CBAG1 refers to a co-foaming agent selected from the group consisting of 1234ze(E), 1336mzz(Z), 1336mzzm(E), 1224yd(Z), 1233zd(E), 1234yf, and two or more combinations thereof.

[0122] CBAG2 refers to a co-foaming agent selected from the group consisting of water, CO2, C1-C6 hydrocarbons (HC), HCFCs, C1-C5 HFCs, C2-C4 hydrohaloolefins, C1-C5 alcohols, C1-C4 aldehydes, C1-C4 ketones, C1-C4 ethers, C1-C4 esters, organic acids, and combinations of two or more of these.

[0123] CCBAG3 refers to a co-foaming agent selected from the group consisting of water, CO2, isobutane, n-butane, isopentane, cyclopentane, cyclohexane, trans-dichloroethylene, ethanol, propanol, butanol, acetone, dimethyl ether, diethyl ether, dimethoxymethane, diethoxymethane, methyl formate, difluoromethane (HFC-32), fluoroethane (HFC-161), difluoroethane (HFC-152), trifluoroethane (HFC-143), 1,1,1,2-tetrafluoroethane (HFC-134a), pentafluoroethane (HFC-125), pentafluoropropane (HFC-245), hexafluoropropane (HFC-236), heptafluoropropane (HFC-227ea), pentafluorobutane (HFC-365), hexafluorobutane (HFC-356), and any two or more combinations thereof.

[0124] NR means not requested.

[0125] Table 5-1

[0126] Table 5-2 Table 5-3

[0127] Table 5-4

[0128] Table 5-5

[0129] Table 5-6

[0130] Table 5-7

[0131] Table 6-1

[0132] Table 6-2

[0133] Table 6-3

[0134] How to form vesicles To form the foams of the present invention, it is intended that one or more of the various known techniques for forming thermoplastic foams may be used, taking into account the disclosures contained herein, and the foams of the present invention include each of foams 1-4 and foaming compositions 1-11, all such techniques and all foams formed thereby, or all foams within the broad scope of the present invention. For clarity, it should be noted that all definitions of foams in the following table begin with the letter F, in contrast to the foams defined in the paragraph of the above summary of the invention which begins with the capital letter Foamable Composition.

[0135] Generally, the formation process involves first introducing a blowing agent of the present invention, containing each of blowing agents 1 to 31, into a PEF polymer of the present invention containing each of TPP1 to TPP22, thereby forming a foamy PEF composition containing PEF and a blowing agent. One preferred method for forming the foamy PEF composition of the present invention is to plasticize the PEF, which preferably involves heating the PEF to its melting temperature, preferably to a temperature higher than its melting temperature, and then exposing the PEF melt to the blowing agent under conditions that are effective in incorporating (preferably by solubilizing) a desired amount of blowing agent into the polymer melt.

[0136] In a preferred embodiment, the foaming method of the present invention includes providing an effervescent composition of the present invention containing each of FC1 to FC11, and foaming the provided effervescent composition. In a preferred embodiment, the foaming method of the present invention includes providing an effervescent composition of the present invention containing each of FC1 to FC11, and extruding the provided effervescent composition to form a foam of the present invention containing each of foams 1 to 4 and each of foams F1 to F8.

[0137] The foaming process of the present invention may include a batch process, a semi-batch process, a continuous process, and a combination of two or more of these. A batch process generally involves preparing at least a portion of an expandable polymer composition containing each of FC1 to FC11 in a storable state, and then using that portion of the expandable polymer composition at some point in the future to prepare a foam. A semi-batch process includes, all in a single process, preparing at least a portion of an expandable polymer composition containing each of FC1 to FC11, and intermittently expanding that expandable polymer composition into a foam containing each of foams 1 to 4 and each of foams F1 to F11. For example, U.S. Patent No. 4,323,528, incorporated herein by reference, discloses a process for producing a thermoplastic foam via a cumulative extrusion process. Accordingly, the present invention includes a process comprising: 1) mixing a PEF thermoplastic polymer containing each of TPP1 to TPP22 and a blowing agent of the present invention containing each of blowing agents 1 to 31 under conditions for forming a foamy PEF composition; 2) extruding the foamy PEF composition containing each of FC1 to FC11 into a holding zone maintained at a temperature and pressure that does not cause the foamy composition to foam, wherein the holding zone preferably includes a die defining an orifice that opens into a lower pressure zone in which the foamy polymer composition containing each of FC1 to FC11 foams, and an openable gate that closes the die orifice; 3) periodically opening the gate while substantially simultaneously applying mechanical pressure to the foamy polymer composition containing each of FC1 to FC11 with a movable ram, thereby discharging it from the holding zone through the die orifice to a lower pressure zone; and 4) expanding the discharged foamy polymer composition under the influence of a blowing agent to form a foam containing each of foams 1 to 4 and each of foams F1 to F8.

[0138] The present invention also allows the use of a continuous process to form a foam. For example, such a continuous process includes forming a foamable PEF composition containing each of FC1 to FC11, and then expanding the foamable PEF composition without substantial interruption. For example, a foamable PEF composition containing each of FC1 to FC11 can be prepared in an extruder by heating a selected PEF polymer resin containing each of TPP1 to TPP22 to form a PEF melt, incorporating a blowing agent of the present invention containing each of blowing agents 1 to 31 into the PEF melt, preferably by solubilizing the blowing agent in the PEF melt at an initial pressure, to form a foamable PEF composition containing a substantially homogeneous combination of PEF and a blowing agent containing each of FC1 to FC11, and then extruding the foamable PEF composition through a die into a zone of selected foaming pressure, foaming the foamable PEF composition and expanding it under the influence of the blowing agent into a foam containing each of foams 1 to 4 and each of foams F1 to F8 described below. Optionally, a foaming PEF composition comprising a PEF polymer containing each of FC1 to FC11 and an incorporated blowing agent containing each of blowing agents 1 to 31 may be cooled before the composition is extruded through a die to improve specific desired properties of the resulting foam, which includes each of foams 1 to 6 and each of foams F1 to F8.

[0139] This method can be carried out, for example, using a general type of extrusion apparatus disclosed in Figure 1. Specifically, the extrusion apparatus may include a raw material supply hopper 10 for holding the PEF polymer 15 of the present invention, each of TPP1 to TPP22, and one or more optional components (which may be added in the hopper or optionally elsewhere in the process with the PEF, depending on the specific needs of the user). The supply material 15, excluding the blowing agent, can be fed into the hopper and delivered to a screw extruder 10. The extruder 20 may include thermocouples (not shown) positioned at three points along its length and a pressure sensor (not shown) at the discharge end 20A of the extruder. A mixer section 30 may be located at the discharge end 20A of the extruder to receive the blowing agent components of the present invention, each of blowing agents 1 to 31, via one or more metering pumps 40A and 40B, and to mix these blowing agents into the PEF molten material in the mixer section. Sensors (not shown) may be included to monitor the temperature and pressure of the mixer section 30. The mixer section 30 can discharge the molten foaming agent composition of the present invention, including each of FC1 to FC11, into a pair of series-oriented molten coolers 50, with temperature sensors (not shown) located in each cooler to monitor the molten temperature. The molten material is then extruded through a die 60, which also has temperature and pressure sensors (not shown) to monitor the pressure and temperature at the die. The die pressure and temperature can be varied according to the requirements of each specific extrusion application for producing the foam 70 of the present invention, including each of foams 1 to 4 and each of foams F1 to F8 described below. The foam can then be carried out of the extrusion equipment by a conveyor belt 80.

[0140] The foaming polymer compositions of the present invention, each comprising FC1 to FC11, may optionally contain additional additives such as nucleating agents, foam control agents, glass and carbon fibers, dyes, pigments, fillers, antioxidants, extrusion aids, stabilizers, antistatic agents, flame retardants, IR damping agents, and thermal insulation additives. Examples of nucleating agents include, in particular, materials such as talc, calcium carbonate, and sodium benzoate, as well as chemical blowing agents such as azodicarbonamide or sodium bicarbonate and citric acid. Examples of IR damping agents and thermal insulation additives include, in particular, carbon black, graphite, silicon dioxide, metal flakes, or powders. Examples of flame retardants include, in particular, brominated materials such as hexabromocyclodecane and polybrominated biphenyl ethers. Each of the above additional optional additives can be introduced into the foam at various times and locations during the process according to known techniques, and all such additives and methods of introduction are within the broad scope of the present invention.

[0141] foam In a preferred embodiment, the foam of the present invention is formed using a commercially available extruder and has the properties shown in Table 4 below, the values ​​of which are measured as described in the examples of this specification.

[0142] [Table 7]

[0143] Foams that fall within the scope of the present invention and offer specific advantages are listed in Table 5 below, where all numerical values ​​in the table are understood to be preceded by the word “about”, and the symbol NR means “not required”.

[0144] [Table 8-1]

[0145] [Table 8-2]

[0146] Table 8-3

[0147] Table 8-4

[0148] Table 8-5

[0149] Table 8-6

[0150] Table 8-7

[0151] Table 8-8

[0152] Table 8-9

[0153] Table 8-10

[0154] Table 8-11

[0155] Table 8-12

[0156] Table 8-13

[0157] Table 8-14

[0158] Table 8-15

[0159] Table 8-16

[0160] Table 8-17

[0161] Table 8-18

[0162] Table 8-19

[0163] Table 8-20

[0164] Table 8-21

[0165] Table 8-22

[0166] Table 8-23

[0167] Table 8-24

[0168] Table 8-25

[0169] Table 8-26

[0170] Table 8-27

[0171] Table 8-28

[0172] Table 8-29

[0173] Table 8-30

[0174] Table 8-31

[0175] Table 8-32

[0176] Table 8-33

[0177] Table 8-34

[0178] Table 8-35

[0179] Table 8-36

[0180] Table 8-37

[0181] Table 8-38

[0182] Table 8-39

[0183] Table 8-40

[0184] Table 8-41

[0185] Table 8-42

[0186] Table 8-43

[0187] [Table 8-44]

[0188] [Table 8-45]

[0189] [Table 8-46]

[0190] [Table 8-47]

[0191] [Table 8-48]

[0192] [Table 8-49]

[0193] The foams of the present invention have broad applicability. The foams, each comprising foams 1-4 and foams F1-F8, offer unexpected advantages in applications requiring low density and / or good compression and / or tensile and / or shear properties, and / or long-term stability, and / or sustainable sourcing, and / or being made from recycled materials and recyclable. Specifically, the foams, each comprising foams 1-6 and foams F1-F8, offer unexpected advantages in wind energy applications (wind turbine blades (shear webs, shells, cores, and routes)), marine applications (hulls, decks, superstructures, bulkheads, longitudinal members, and interiors), industrial lightweight applications, and automotive and transport applications (interiors and exteriors of automobiles, trucks, trains, aircraft, and spacecraft).

[0194] PEF:PET copolymers can be formed by any means known to those skilled in the art, including but not limited to the procedures described in the examples herein.

[0195] The foams of the present invention, each comprising foams 1 to 4, are formed from any of the following: PEF homopolymer, PEF copolymer, PEF:PET copolymer, or a combination / mixture thereof.

[0196] In a preferred embodiment, each of the foams 1 to 4 may be formed from a PEF homopolymer having at least 99.5% by weight or at least 99.9% by weight of an ethylene furanoate moiety.

[0197] The foams of the present invention, each comprising foams 1 to 3, are intended to be formed from a PEF copolymer, which is a polymer comprising a PEF copolymer having about 0.5% to about 99% by weight of an ethylene furanoate moiety. The present invention comprises foams, each comprising foams 1 to 3, and the thermoplastic polymer essentially consists of the components listed in the following table.

[0198] [Table 9-1]

[0199] [Table 9-2]

[0200] The foam of the present invention, comprising each of foams 1 to 3, may include closed-cell walls comprising each of the thermoplastic polymers of the present invention, comprising each of TMP1 to TMP12 as described in the table above.

[0201] With respect to these embodiments of the present invention, including PEF copolymers, it is intended that those skilled in the art, taking into account the teachings contained herein, can select the type of copolymer material to be used in amounts within each of the ranges described herein to achieve the desired enhancement / modification of the polymer without excessive experimentation.

[0202] The TMP of the present invention is intended to be formed to have a variety of physical properties, including polymer properties within the following ranges, as measured as described in the examples of this specification.

[0203] [Table 10]

[0204] Generally, it is intended that those skilled in the art can formulate PEF polymers within the range of the above properties without excessive experimentation, taking into account the teachings contained herein. However, in preferred embodiments, PEF polymers according to the present invention (including the PEF:PET copolymer of the present invention) having these properties are achieved by using one or more of the above synthesis methods in combination with various known auxiliary processing techniques, including treatment with chain extenders such as PMDA and / or SSP treatment.

[0205] An example of a process for chain extension treatment of polyester is provided in the literature “Recycled poly(ethylene terephthalate) chain extension by a reactive extrusion process,” Firas Awaja, Fugen Daver, Edward Kosior, 16 August 2004, https: / / doi.org / 10.1002 / pen.20155, which is incorporated herein by reference. As described in U.S. Publication No. 1009 / 0264545, incorporated herein by reference, chain extenders are generally compounds that are at least bifunctional with respect to reactive groups that can react with terminal groups or functional groups in polyester to extend the length of polymer chains. In particular cases, as disclosed herein, such treatments can favorably increase the average molecular weight of the polyester and improve its melt strength and / or other important properties. The degree of chain extension achieved is at least in part related to the structure and functionality of the compound used. A variety of compounds are useful as chain extenders. Non-limiting examples of chain extenders include trimellitic anhydride, pyromellitic dianhydride (PMDA), trimellitic acid, its haloformyl derivatives, or compounds containing polyfunctional epoxy (e.g., glycidyl) or oxazoline functional groups. Nanocomposite materials, such as finely dispersed nanoclay, may optionally be used to control viscosity. Commercially available chain extenders include Clariant's CESA-Extend, BASF's Joncryl, or Arkema's Lotader. The amount of chain extender may vary depending on the type and molecular weight of the polyester component. The amount of chain extender used to process the polymer can vary widely, in preferred embodiments ranging from about 0.1 to about 5% by weight, or preferably from about 0.1 to about 1.5% by weight. Examples of chain extenders are also described in U.S. Patent No. 4,219,527, which is incorporated herein by reference.

[0206] An example of a process for SSP treatment of poly(ethylene furanoate) is found in the paper "Solid-State Polymerization of Poly(ethylene furanoate) Biobased Polyester, I: Effect of Catalyst Type on Molecular Weight Increase." Provided to Nejib Kasmi, Mustapha Majdoub, George Z. Papageorgiou, Dimitris S. Achilias, and Dimitrios N. Bikiaris, which are incorporated herein by reference.

[0207] The foams of the present invention have broad applicability. The foams of the present invention, including each of foams 1 to 10, have unexpected advantages in applications requiring low density and / or good compression and / or tensile and / or shear properties, as well as / or long-term stability, as well as / or sustainable sourcing, and / or being made from recycled materials and recyclable. Specifically, the foams of the present invention, including each of foams 1 to 10, have unexpected advantages in wind energy applications (wind turbine blades (shear webs, shells, cores, and nacelles)), marine applications (hulls, decks, superstructures, bulkheads, longitudinal members, and interiors), industrial lightweight applications, automotive and transport applications (interiors and exteriors of automobiles, trucks, trains, aircraft, and spacecraft), fixed building structures, and sporting goods.

[0208] The size and shape of the foam used in this foamed article can be broadly varied within the scope of the present invention depending on the intended use of the article, and all such sizes and shapes are within the scope of the present invention. In many applications, the foam takes the form of a three-dimensional shape in which the length and / or width is much greater than the thickness. In other applications, the form of the article can be characterized as a block, slab, panel, etc., or as a specific shape such as an I-beam, U-shape, or other particular shape.

[0209] Foamed articles The foam of the present invention may also be formed into a foam article comprising the foam of the present invention, the surface of which at least a portion is surface-finished. For illustrative purposes only, rather than as an limitation, Figure 2 illustrates a form in which the foam article is a general shape of a sheet or panel having surface material on each side of the sheet or panel. In the illustrated embodiment, the foam article according to the present invention comprises a core 1 of the PEF foam of the present invention comprising each of the foams 1 to 4 defined below, at least one reinforcing surface material 2, and at least one connecting and / or integrating layer 3. Those skilled in the art will understand, considering the teachings contained herein, that the connecting / integrating layer may include, for example, a layer of adhesive, or may be formed by integrating the core material and the surface material without using a separate adhesive, for example, by melting the surfaces of two materials together to form a connecting / integrating region. The surface material may be any material suitable for the intended application, as described above, but in many applications, the surface material 2 is a sheet or film of a fibrous material as described above. The fibers of the preferred surface material 2 may be in the form of a woven mat or a nonwoven mat (or a mat including a combination of woven and nonwoven fibers), for example, including either a woven or nonwoven mat, and the fibers may be oriented or unoriented (i.e., random). In embodiments in which the fibers of the surface material are oriented, the orientation may include unidirectional, bidirectional, biaxial, triaxial, quaternary, and any combination thereof.

[0210] The connecting / integrating film, layer, or region 3 may be of any material and of any thickness necessary to adhere or integrate the surface material 3 with the core 1. Furthermore, although the film or layer 3 is generally shown to be between the surface material 2 and the core 1, it will be understood and recognized by those skilled in the art that the connecting layer or film generally extends into each of the foam core 1 and the surface material 2. In certain preferred embodiments, the film or layer 3 may include an adhesive material such as an epoxy adhesive that bonds the core 1 and the surface sheet 2 together. Other adhesive resins that may be used to bond the surface material to the foam include polyurethane, vinyl ester, polyester, cyanate ester, urethane acrylate, bismaleimide, polyimide, silicone, phenolic resin, polypropene, caprolactam, and any two or more combinations thereof. Generally, the process of forming the foam article of the present invention involves steps that provide a strong chemical and / or physical bond between the surface material 2 and the foam 1, and all such steps are within the scope of the present invention.

[0211] In a preferred embodiment, the surface material 2 may be the same or different and includes a plurality of interconnecting sheets or mats bonded together by appropriate means, including an interconnecting layer of adhesive or resin or interconnecting regions formed by material integration (e.g., melting together to form an integrated region). In such embodiments, the number of interconnecting sheets constituting the surface material 2 can vary widely, and in a preferred embodiment, the surface material is intended to include 2 to 10 interconnecting sheets, and more preferably about 3 to about 5 interconnecting sheets.

[0212] It is understood that the dimensions of the foam article may vary widely, but in preferred embodiments involving use in wind turbine applications, the surface sheet may vary between approximately 0.1 mm and 3 mm, or between approximately 0.4 mm and 1.5 mm. Furthermore, the relative thickness of the foam compared to the surface sheet may vary over a wide range depending on the specific application, and those skilled in the art can make an appropriate selection considering the teachings contained herein, and it is generally understood that the thickness of the surface sheet is less than the thickness of the foam.

[0213] Preferred materials used to form the foamed articles of the present invention are described in more detail below.

[0214] Surface material The foamed articles of the present invention include a surface material that can have a wide variety of dimensions, the dimensions used depending on the specific needs of the application in which the foamed articles are used, and all articles having such dimensions are within the scope of the present invention.

[0215] The materials forming the surface material can also vary widely depending on the specific use intended for the foam article, and here again all such materials are within the scope of the present invention. For example, the surface material used in the foam article comprises one or more fibrous sheets or mats, and the fibrous portion can be formed from a wide variety of materials, including, for example, glass fibers (preferably impregnated with resin and / or polymer), other natural fibers (such as cellulose and other plant-derived materials), mineral fibers (such as quartz), metal fibers or films, carbon fibers (preferably impregnated or reinforced with one or more polymers, including thermoplastic polymers and / or thermosetting polymers), synthetic fibers such as polyester (for example, including fibers containing furan-based polyesters disclosed in U.S. Publication No. 2015 / 0111450, which is incorporated herein by reference), polyethylene, aramid, Kevlar, and any and all combinations thereof.

[0216] Specific use The foam articles of the present invention have broad utility. The foam articles of the present invention have unexpected advantages in applications requiring low density and / or good compression and / or tensile and / or shear properties, and / or long-term stability, and / or sustainable sourcing, and / or being made from recycled materials and recyclable. Specifically, the foam articles have unexpected advantages in fluid energy transfer components, for example, in wind and water energy transfer applications (e.g., wind turbine blades (shear webs, shells, cores, and nacelles) for transferring wind energy from stationary or moving devices located in the air, and vortices, tides, oceans, hydrofoils and kites for recovering water kinetic energy from stationary or moving devices located in water), marine applications (hulls, decks, superstructures, bulkheads, longitudinal members, and interiors), industrial lightweight applications, automotive and transport applications (interiors and exteriors of automobiles, trucks, trains, aircraft, and spacecraft), and packaging applications.

[0217] Referring particularly to Figures 3 and 4A, 4B, and 4C, the foam articles of the present invention can be used in the rotor blade 10 at any and all positions along the length of the blade from the blade root 30 to the blade tip 32 located on the opposite side of the blade root 30, and at any position along the main shell, including on the pressure side 34, on the suction side 36, and at all positions extending from the leading edge 26 to the trailing edge 28 of the rotor blade 10. Furthermore, the foam articles of the present invention can be used in all or some of the longitudinally extending structural components of the rotor blade 10 configured to increase the rigidity, buckling resistance, and / or strength of the rotor blade 10, such as longitudinally extending spur caps 20, 22 configured to engage with the opposing inner surfaces 35, 37 of the positive pressure surface 34 and negative pressure surface 36 of the rotor blade 10, and in one or more shear webs 24 positioned between the spur caps 20 and 22 to form a beam-like configuration. The spur caps 20 and 22 may generally be designed to resist bending stresses during the operation of the wind turbine 10 and to minimize blade tip deflection and / or other loads acting on the rotor blade 10 in the span direction (a direction parallel to the span 23 of the rotor blade 16). However, in other applications, it is understood that the spur caps may also be oriented at any angle transverse to the span direction axis, including an angle of about 90 degrees with respect to the span direction axis. Similarly, the spur caps 20 and 22 may also be designed to resist span direction compression or tension that occurs during the operation of the wind turbine 6. Due to the unexpected combination of light weight and high strength of the foam and foam articles, such foam and foam articles can be advantageously utilized in the root portions of blades, as well as in spurs and caps used on rotor blades.

[0218] The following foam usage table contains some identifications of preferred uses for some of the preferred foam articles of the present invention, including foams and surface materials for foams, where the column heading "Foam Article Number" refers to a foam article containing the specific foam indicated as identified above.

[0219] [Table 11] [Examples]

[0220] Without limiting the entire scope of the present invention, the applicants conducted a series of experiments to demonstrate the usefulness of the PEF homopolymers and PEF-based copolymers of the present invention and to compare the performance of foams prepared according to the present invention with foams prepared using blowing agents other than HFC-152a and PET foams prepared using HFC-152a. These tests included the synthesis of a series of PET polymers covering a range of physical properties such as molecular weight, crystallinity, and melting point. The applicants also prepared a series of PEF polymers (including homopolymers and copolymers) over a similar range of physical properties. A series of foams were prepared using HFC-152a of the present invention as the blowing agent. Foams prepared using other materials as blowing agents were also prepared and tested. A consistent set of processing conditions was used for a given range of comparable polymer properties.

[0221] The foaming conditions were selected to ensure proper expansion.

[0222] Throughout the embodiments of this application, the foams thus produced were tested, and the density of the foams was determined using a method generally corresponding to ASTM D71, except that hexane was used as a substitute for water. To facilitate comparison of the densities of the foams produced in these embodiments, the applicants report the foam density as relative foam density (RFD), which is the density of the foam measured above divided by the density of the starting polymer. Herein, all foam densities, regardless of whether they originate from PEF or PET homopolymer or PEF-PET copolymer, are corrected by the density of PEF polymer, which is 1.43 g / cc, and is about 7% lower than that of PET. In this way, when the strengths of various polymer foams are compared at the same RFD, they are also compared at the same overall density.

[0223] Furthermore, each of the foams produced in these examples was tested to determine its tensile and compressive strengths. The tensile and compressive strength measurements were based on the guidelines specified in ASTM C297 and ISO 844, respectively, and the measurements in each case were performed in the direction of reduced pressure.

[0224] The details of each of these experimental results will be explained in detail in the following examples.

[0225] Example 1A - Preparation of PEF of MW114000 using PMDA chain extender and SSP Bio-based polyethylene furanoate homopolymers were prepared by esterification and polycondensation of 2,5-franzicarboxylic acid with monoethylene glycol using the additives and polymer formation procedure generally described in Synthesis Example 1A below.

[0226] The homopolymer produced in this manner, called PEFEx1, was tested and found to have the characteristics reported in Table Ex1A below. 1

[0227] [Table 12]

[0228] The PEF polymer thus produced is referred to as PEFEx1 in these examples. ------------- 1Throughout these examples, the molecular weights determined and referenced herein refer to molecular weight determination by diffusion-ordered nuclear magnetic resonance spectroscopy (DOSY NMR) as described in "Application of 1H DOSY NMR in Measurement of Polystyrene Molecular Weights," VNU Journal of Science: Natural Sciences and Technology, Vol.36, No.2 (2020), 16-21 June 2020, Nam et a, except that the solvent used differs. The above reference used 3 mg of polystyrene and 0.5 mL of deuterated chloroform. In these examples, NMR measurements were performed using the soluble portion of 2-3 mg of polymer in a mixture of 0.6 mL of 50 vol% deuterated chloroform + 50 vol% trifluoroacetic acid.

[0229] Comparative Examples C1A, C1B, and C1C-PEFEx1, and Preparation of PEF Foam Using Isopentane, Cyclopentane, and CO2 as Foaming Agents For each of these comparative examples, 1 gram of PEFEx1 in a glass container was placed in an autoclave and dried under vacuum at 130°C for 6 hours. The dried polymer was then cooled to room temperature and placed in a glass container in the autoclave. The amounts of blowing agent shown in the table below were pumped into the autoclave containing the dried polymer, and the autoclave was then heated to a temperature of approximately 240°C and a pressure exceeding approximately 610 psig to melt the polymer. The polymer / blowing agent was maintained in a molten state at the molten pressure and temperature for the approximate period shown in the table (hereinafter referred to as "melting time," MTime) (either 60 minutes or 15 minutes). The temperature (MTemp) and pressure (MP) of the molten material / blowing agent were then reduced to the pre-foaming temperature (PFT) over approximately 5-15 minutes, and then maintained at approximately this temperature and pressure for approximately 30 minutes to bring the amount of blowing agent incorporated into the molten material to equilibrium under these conditions. Next, the temperature and pressure inside the autoclave were rapidly reduced to ambient conditions (approximately 22°C and 1 atmosphere) (the pressure reduction took about 10 seconds, and the temperature reduction using chilled water took about 1 to 10 minutes) to induce foaming. The foam thus produced was tested, and the following properties were determined. • Compressive strength ("CS") (measured perpendicular to a plane according to ISO 844) • Tensile strength ("TM") (measured perpendicular to a plane according to ASTM C297) • Relative foam density ("RFD").

[0230] As used herein, RFD is the density of the manufactured foam divided by the density of the starting polymer. The density is measured using a method generally corresponding to ASTM D71, except that in these examples hexane is used instead of water for substitution.

[0231] The foams produced in these comparative examples C1A, C1B, and C1C were tested and found to have the characteristics reported in Table C1 below.

[0232] [Table 13]

[0233] Example 2 - Preparation of PEF of MW49,000 using PMDA chain extender and SSP A bio-based polyethylene furanoate homopolymer was prepared by esterification and polycondensation of 2,5-franzicarboxylic acid with monoethylene glycol using the additives and polymer formation procedure described in Synthesis Example 2 below.

[0234] The homopolymer produced in this manner, called PEFEx2, was tested and found to have the characteristics reported in Table Ex2 below.

[0235] [Table 14]

[0236] The PEF polymer thus produced is referred to as PEFEx2 in these examples.

[0237] Example 2A-PEX2 and Preparation of PEF foam using HFC-152a as a foaming agent The procedure for producing a foam as described in Comparative Example 1 was repeated, except that the blowing agent was HFC-152a and the process conditions were as shown in Table E2A below. The foam thus produced was observed to be a good, high-quality foam and was subsequently tested and found to have the properties reported in Table E2B below, along with the results from Comparative Examples 1A, 1B, and 1C for ease of comparison.

[0238] [Table 15]

[0239] The PEF polymer used to form the foam in Example 2 had a molecular weight less than half that of the polymer used to produce the comparative foam. Generally, using low molecular weight materials to produce foams tends to result in foams with inferior strength compared to foams made from the same thermoplastic resin but with higher molecular weights. Also, generally speaking, the strength properties of foams tend to decrease as density decreases. Despite these general trends, the foam produced according to the present invention surprisingly exhibits dramatically superior properties compared to the comparative foam. This result is even more surprising considering that (1) the molecular weight of the polymer material used to produce the foam in this example was less than half that of the polymer material used to form the comparative example, and (2) the foam of the present invention in this example had the lowest density among all the foams in Table E2A. For example, the CS+TS value of the foam in this example was 3.17, which is almost twice as high as the foam foamed with isopentane, even though the isopentane foam has a higher density and was made from a polymer with a molecular weight of 114,000.

[0240] Comparative Example 2A - Preparation of a PET homopolymer with a molecular weight of approximately 81 kg / mol and a crystallinity of 43 using PMDA and SSP 1 As described in detail in Synthesis Example C1 below, a PET homopolymer was prepared by polycondensation using the procedure described in Synthesis Example C1, resulting in a polymer product with a molecular weight of approximately 81 kg / mol, and a polymer with a molecular weight of 80,871, identified below as PETC1A. ------------- 1 The designation of an example as “comparative” in this specification should not be interpreted as indicating that the example represents any item of the prior art, but rather is presented solely for comparison with preferred embodiments of the invention presented in other examples.

[0241] The PET homopolymer designated herein as PETC1A was tested and found to possess the characteristics reported in Table C1A below.

[0242] [Table 16]

[0243] As can be seen from the table above, the PET homopolymer was produced using the preferred high-crystallinity embodiment of the present invention, and therefore exhibits unexpectedly high strength in the PET foam produced using the blowing agent of the present invention compared to PET foam produced from PET polymers that do not use this embodiment of the present invention.

[0244] Comparative Examples C1B1~C1B4: Preparation of PET foam using PETC1A with HFC-152a blowing agent for a melting time of 60 minutes. In a series of runs, 1 gram of polymer PETC1A in a glass container was placed in a 60 cc autoclave and then dried under vacuum at 130°C for 6 hours. The dried polymer was then cooled to room temperature. In each case, a blowing agent (shown in Table C1B below) was then pumped into the autoclave containing the dried polymer, and the autoclave was subsequently heated to melt the polymer, with the temperature, pressure, and time listed in Table C1B below. After the indicated melting time, the temperature and pressure of the molten material / blowing agent were then reduced over approximately 5 to 15 minutes to the pre-foaming temperature and pre-foaming pressure shown in Table C1B. The autoclave was then maintained at approximately this temperature and pressure for approximately 30 minutes to ensure that the amount of blowing agent incorporated into the molten material under these conditions reached equilibrium. The conditions used, including the amount of blowing agent and the melting temperature and pressure, were determined after several tests based on the ability to form an acceptable foam with an RFD value in the range of approximately 0.05 to approximately 0.2. Next, the temperature and pressure inside the autoclave were rapidly reduced to ambient conditions (approximately 22°C and 1 atmosphere) (the pressure reduction took about 10 seconds, and the temperature reduction using cold water took about 1 to 10 minutes), causing foaming.

[0245] The PET foam thus produced in this Example C1B was tested and found to have the properties reported in Table C1B below, which for comparative purposes includes the foam of the present invention according to Example 2A above.

[0246] [Table 17]

[0247] As shown in Table C1B above, the foam of the present invention, prepared using the HFC-152a blowing agent and the preferred PEF homopolymer of the present invention, shows dramatically superior results compared to foam prepared from PET homopolymer when HFC-152a is used as the blowing agent. For example, the CS+TS value of the foam of Example 2A according to the present invention is 3.17, which is almost three times higher than the foam prepared from PET, which was foamed with HFC-152a but has a molecular weight about twice that of the PEF foam. This is remarkable and a very advantageous result.

[0248] Examples 4-6 - Preparation of PEF foam using PEF having 25,000-150,000 MW Repeat Example 1, except that the conditions and materials are changed as shown in Tables E4 to E10 below, but all values ​​are understood to be "approximately", and the weight % of HFC-152a refers to the weight % based on the total weight of the blowing agent used to produce the foam.

[0249] [Table 18] * The weight percentage of the PEF portion in the polymer, and the Cr percentage, refer to the crystallinity percentage in the polymer. ** A - Acceptable

[0250] [Table 19] * The weight percentage of the PEF portion in the polymer and Cr% indicate the crystallinity percentage in the polymer. ** A - Acceptable

[0251]

Table 20

[0252] In each case of the above Tables E5 - E6, the thermoplastic polymer used to produce the foam had characteristics within the following ranges (measured according to the same procedure as specified above in Comparative Example 1). Glass transition temperature - 85 to 95 °C Melting temperature - 200 to 240 °C Decomposition temperature - 320 to 400 °C Crystallinity - 30 to 60%

[0253] It is observed that all the foams produced in this way according to these examples are foams of acceptable quality.

[0254] Synthesis Example 1 - Preparation of a PEF homopolymer having an MW of about 90 kg / mol or more using PMDA and SSP To obtain a PEF homopolymer of 96,078 g / mol MW, 75 grams of 2,5-franzicarboxylic acid (FDCA) and 55 grams of monoethylene glycol (EG) were added. The reactants were added to a 500 mL cylindrical steel reactor equipped with an overhead stirrer and a distillation / condensation apparatus. After vacuuming and backfilling with nitrogen, 0.228 grams of titanium(IV) isopropoxide catalyst were added to the flask. The flask was then lowered into a salt bath at 180°C, and overhead mixing was started at 200 rpm under a nitrogen atmosphere. After 2.5 hours, the bath temperature was raised to 220°C. Under nitrogen, after 30 minutes at this temperature, vacuum was initiated. After 40 minutes under vacuum, the temperature was raised to 250°C and continued for 1 hour. Under a nitrogen stream, PMDA (0.5732 g) was slowly added over approximately 5 minutes. After mixing at this temperature for a further 30 minutes, the reaction was stopped. To perform SSP, aliquots of the product were ground and heated in a rotary evaporator under vacuum at 180°C for 3 days to produce a PEF homopolymer as reported below. The product was removed from the container. γ-valerolactone was added to dissolve the polymer remaining in the reactor and on the impeller. The mixture was stirred at 190°C for several hours. γ-valerolactone was distilled from the polymer under vacuum to obtain a solid. To perform SSP, aliquots of the product were ground and heated in a rotary evaporator under vacuum at 180°C for 3 days to produce a PEF homopolymer with a molecular weight of 96,078.

[0255] Synthesis Example 2 - Preparation of PEF homopolymer with approximately 49 kg / mol MW using PMDA and SSP PEF homopolymers were prepared using the same additives and basic polymer formation procedure as those used in Synthesis Example 1, achieving a polymer molecular weight of approximately 49,000 g / mol. Specifically, a 49 kg / mol MW PEF homopolymer was formed by esterification and polycondensation of 75 g of 2,5-franzicarboxylic acid (FDCA) and 59.8 g of monoethylene glycol (EG). The reactants were added to a 500 mL cylindrical steel reactor equipped with an overhead stirrer and a distillation / condensation apparatus. After vacuuming and backfilling with nitrogen, 0.067 g of titanium(IV) isopropoxide catalyst was added to the flask. The flask was then lowered into a salt bath at 180°C, and overhead mixing was started at 200 rpm under a nitrogen atmosphere. After 2.5 hours, the bath temperature was raised to 220°C. Under nitrogen, after 30 minutes at this temperature, vacuum was initiated. After 40 minutes under vacuum, the temperature was raised to 230°C and continued for 1 hour. Under a nitrogen stream, 0.58 grams (0.7 wt%) of PMDA was slowly added over approximately 5 minutes. To perform SSP, an aliquot (30 g) of the product was pulverized and heated in a rotary evaporator under vacuum at 180°C for 3 days to produce a PEF homopolymer as reported in Table SEx2 below.

[0256] [Table 21]

[0257] Preparation of PET homopolymer with a molecular weight of 80.9 kg / mol using synthesis example C1-PMDA and SSP. PET homopolymers were prepared by polycondensation to obtain a product with a molecular size of 61.1 kg / mol. Approximately 93 grams (0.366 mol) of bis(2-hydroxyethyl) terephthalate (BHET) were added to a 500 mL round-bottom flask. After vacuuming and refilling with N2, the flask was lowered into a salt bath at 180°C, and overhead mixing was started at 100 rpm under N2 flow. After heating under N2 for 3 hours, 0.123 grams (0.0004 mol) of titanium isopropoxide catalyst were added to the flask. After 50 minutes, the bath temperature was raised to 285°C. Under N2, after 1.5 hours at this temperature, vacuum was started and continued for 2 hours. Under N2 flow, pyromellitic dianhydride PMDA (0.49 g, 0.0022 mol) was slowly added over approximately 10 minutes. After mixing at this temperature for a further 30 minutes, the reaction was stopped. An aliquot (30g) of the above product was pulverized, and then solid-phase polymerization was carried out by heating under vacuum at 180°C for 3 days in a rotary evaporator to obtain a polymer having a molecular weight of 81 kg / mol.

Claims

1. A low-density thermoplastic foam, (a) Thermoplastic polymer bubbles comprising a cell wall containing polyethylene furanoate, wherein at least about 50 volume percent of the bubbles are closed cells, and the ethylene furanoate portion is at least 1 mol% of the thermoplastic polymer, (b) A low-density thermoplastic foam comprising HFC-152a contained within the closed cells.

2. The foam according to claim 1, wherein the bubble walls are treated with a chain extender and essentially consist of polyethylene furanoate having a molecular weight of at least about 25,000.

3. The foam according to claim 2, wherein at least about 75% of the bubbles are closed cells.

4. The foam according to claim 3, wherein the ethylene furanoate portion is at least 10% by weight of the thermoplastic polymer.

5. The foam according to claim 2, wherein the foam has a foam density of less than 0.2 g / cc.

6. The foam according to claim 2, wherein the bubble wall essentially consists of polyethylene furanoate having a molecular weight of at least about 90,000.

7. The foam according to claim 1, wherein the one or more foaming agents contained within the closed cells further comprises at least 1234ze(E).

8. A wind energy turbine blade and / or nacelle comprising the foam described in claim 1.

9. A wind energy turbine blade and / or nacelle comprising the foam described in claim 2.

10. A wind energy turbine blade and / or nacelle comprising the foam described in claim 5.

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