Shrinkable Polymer

Abstract

The technology disclosed herein generally relates to polymer compositions that include several different PVOH grades and shrinkable products made therefrom.

Description

[Technical Field]

[0001] The present invention generally contemplates a novel family of polymer compositions for producing water-soluble, biodegradable shrinkable films. [Background technology]

[0002] Shrinkable polymer films are a family of polymeric flexible films used in the packaging of finished goods. The application of heat to the film causes it to shrink tightly around the item placed inside. This process results in a clear, durable, protective barrier around the product. The shrinkage of polymers due to the action of heat can be explained by the memory effect: an oriented and cooled polymer returns to its original relaxed shape when heated, causing the film to shrink. Summary of the Invention

[0003] The inventors of the technology disclosed herein have developed a family of unique, environmentally friendly polymer compositions that have the unique ability to be processed into films with surprisingly excellent shrink properties, and thus can be implemented into a variety of products, such as shrink wrap products, shrink labels, etc. The films of the present invention are also configured to exhibit easy and effective biodegradation in water, thereby reducing environmental pollution. This ability to provide a tight, functional barrier around goods for a variety of applications, while being environmentally friendly, makes the polymers or polymer compositions of the present invention unique and commercially desirable.

[0004] The polymer composition of the present invention is based on a combination of different grades of polyvinyl alcohol (PVOH), each grade differing from the others in at least one property selected from the degree of polymerization and the degree of hydrolysis. Among the numerous PVOH grades available commercially or synthetically produced, the present inventors propose the use of a specific combination of PVOH grades that allows the production of various polymer products with different shrinkage capabilities and decomposition properties under the action of water. Polymer films or sheets produced from the composition of the present invention exhibited shrinkage rates of up to 85% upon heat treatment.

[0005] Thus, in a first aspect, there is provided a polymer composition or polymer blend comprising at least one plasticizer and PVOH, wherein the PVOH is a combination of two or more PVOH grades, each having a degree of hydrolysis in the range of 86-99% and a degree of polymerization in the range of 500-3000.

[0006] The PVOH grades used in accordance with the present invention are referred to as Type 1 PVOH grades, Type 2 PVOH grades, and Type 3 PVOH grades; - Type 1 PVOH grades have a degree of hydrolysis of 98-99% and a degree of polymerization of about 800-1700; - Type 2 PVOH grades have a degree of hydrolysis of 86-89% and a degree of polymerization of about 1400-2600; and - Type 3 PVOH grades have a degree of hydrolysis of 86-89% and a degree of polymerization of 500-800.

[0007] The grade selection may be from among any particular grade type or from among a variety of grade types.

[0008] In some embodiments, the composition comprises three or more PVOH grades.

[0009] In some embodiments, three of the PVOH grades are: - Type 1 PVOH grades with a degree of hydrolysis of 98-99% and a degree of polymerization of approximately 800-1700; - Type 2 PVOH grades with a degree of hydrolysis of 86-89% and a degree of polymerization of about 1400-2600, and - Type 3 PVOH grade with a degree of hydrolysis of 86-89% and a degree of polymerization of 500-800.

[0010] The present invention further provides a composition or blend or mixture comprising three or more PVOH grades selected from: - Type 1 PVOH grades, which contain PVOH with a degree of hydrolysis of 98-99% and a degree of polymerization of about 800-1700; - Type 2 PVOH grades, which include PVOH with a degree of hydrolysis of 86-89% and a degree of polymerization of about 1400-2600, and - Type 3 PVOH grades, which include PVOH with a degree of hydrolysis of 86-89% and a degree of polymerization of 500-800.

[0011] In some embodiments, the composition comprises a blend or mixture comprising three or more PVOH grades selected from Types 1, 2, and / or 3.

[0012] In some embodiments, the composition comprises a blend or mixture comprising three or more PVOH grades selected from Type 1.

[0013] In some embodiments, the composition comprises a blend or mixture comprising three or more PVOH grades selected from Type 2.

[0014] In some embodiments, the composition comprises a blend or mixture comprising three or more PVOH grades selected from Type 3.

[0015] In some embodiments, the composition comprises a blend or mixture comprising one or more PVOH selected from grade type 1, one or more PVOH selected from grade type 2, and one or more PVOH selected from grade type 3.

[0016] In some embodiments, the composition comprises a blend or mixture comprising: - one or more PVOHs chosen from grade type 1 having a molecular weight between 35 and 75 KDa, - one or more PVOHs selected from grade type 2 having a molecular weight between 60 and 120 KDa, and - one or more PVOHs chosen from grade type 3 having a molecular weight between 22 and 35 KDa.

[0017] In some embodiments, the viscosity of a solution of 4 wt. % PVOH Grade Type 1 measured at 20° C. is 8-30 cPs, the viscosity of a solution of 4 wt. % PVOH Grade Type 2 measured at 20° C. is 11-58 cPs, and the viscosity of a solution of 4 wt. % PVOH Type 3 measured at 20° C. is 5-10 cPs.

[0018] In some embodiments, the composition comprises a blend of two or more of the PVOH grades listed in Table 1 designated PVOH Grade Type 1, PVOH Grade Type 2, and PVOH Grade Type 3. TIFF0007818088000001.tif68170

[0019] The at least one "plasticizer" present in the composition of the present invention is a compound used to increase the fluidity or plasticity of the polymer composition of the present invention. The at least one plasticizer is selected from materials that can reduce the glass transition temperature and melting point of the polymer composition under melt extrusion. Without being bound by theory, the plasticizer used can also reduce the melt viscosity, tensile strength, hardness, and density of the molten composition, and increase parameters such as elongation at break, toughness, and dielectric constant.

[0020] The at least one plasticizer used is generally compatible with PVOH to allow mixing without recrystallization after mixing and formulation, and is one that is stable under hot melt extrusion conditions and has sufficient lubricity and stability in the final formulation and film.

[0021] The at least one plasticizer may be selected from glycerol, sorbitol, propylene glycol, polyethylene glycol, and the like, as well as any combination thereof.

[0022] In some embodiments, the at least one plasticizer is glycerol.

[0023] In some embodiments, a composition includes a blend of the PVOH grade types disclosed herein, at least one crosslinking compound, at least one additional bioplastic, and optionally at least one additive.

[0024] In some embodiments, a composition includes a blend of the PVOH grade types disclosed herein, at least one additional bioplastic, at least one additive, and optionally at least one crosslinking compound.

[0025] In some embodiments, a composition includes a blend of the PVOH grade types disclosed herein, at least one crosslinking compound, at least one additional bioplastic, and at least one additive.

[0026] In some embodiments, the compositions comprising the PVOH grade-type blends disclosed herein further comprise: a) at least one cross-linking compound present in an amount in the range of 0 or 0.1 to 20 wt. %, wherein the amount of cross-linking compound may be 0.1 to 15, 0.1 to 10, 0.1 to 9, 0.1 to 8, 0.1 to 7, 0.1 to 6, 0.1 to 5, 0.1 to 4, 0.1 to 3, 0.1 to 2, 0.1 to 1, 1 to 20, 1 to 19, 1 to 18, 1 to 17, 1 to 16, 1 to 15, 1 to 14, 1 to 13, 1 to 12, 1 to 11, 1 to 10, 0.1 to 0.5 wt. %, or the amount may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 wt. %, b) at least one additional bioplastic optionally present in an amount in the range of 0.1 to 50 wt.%, wherein the amount of bioplastic may be 0.1 to 45, 0.1 to 40, 0.1 to 35, 0.1 to 30, 0.1 to 25, 0.1 to 20, 0.1 to 15, 0.1 to 10, 0.1 to 7, 0.1 to 5, 0.1 to 1, 1 to 50, 1 to 40, 1 to 30, 1 to 20, 1 to 10, 1 to 5, 10 to 50, 10 to 40, 10 to 30, or 10 to 20 wt.%; and c) at least one additive in an amount in the range of 0.1 to 20 wt.%, wherein the amount of additive may be 0.1 to 15, 0.1 to 10, 0.1 to 9, 0.1 to 8, 0.1 to 7, 0.1 to 6, 0.1 to 5, 0.1 to 4, 0.1 to 3, 0.1 to 2, 0.1 to 1, 1 to 20, 1 to 19, 1 to 18, 1 to 17, 1 to 16, 1 to 15, 1 to 14, 1 to 13, 1 to 12, 1 to 11, 1 to 10, 0.1 to 0.5 wt.%, or the amount may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 wt.%, Includes:

[0027] The amount of PVOH grades combined can be 30-99 wt %. In some embodiments, the amount can be 30-95, 30-90, 30-85, 30-80, 30-75, 30-70, 30-65, 30-60, 30-55, 30-50, 30-45, 30-40, 30-35, 40-95, 45-95, 50-95, 55-95, 60-95, 65-95, 70-95, 75-95, 80-95, or 85-95 wt %.

[0028] The amount of PVOH grades combined can be 30-99 wt %. In some embodiments, the amount can be 30-95, 30-90, 30-85, 30-80, 30-75, 30-70, 30-65, 30-60, 30-55, 30-50, 30-45, 30-40, 30-35, 40-95, 45-95, 50-95, 55-95, 60-95, 65-95, 70-95, 75-95, 80-95, or 85-95 wt %.

[0029] The amount of each PVOH grade in the combination of PVOH grades can be 10-80 wt. %. In some embodiments, the amount can be 10-55, 10-50, 10-45, 10-40, 10-35, 10-30, 10-25, 10-20, 10-15, 20-60, 20-55, 20-50, 20-45, 20-40, 20-35, 20-30, 30-60, 30-50, 30-40, 40-60, 40-50, 50-60 wt. % or 10, 20, 30, 35, 36, 37, 40, 47, 53, 57, 61, 70, or 79 wt. %.

[0030] The total amount of any PVOH grade combination used in the compositions of the present invention should be 30-99 wt % as disclosed herein, and therefore the amount of each grade type constituting the PVOH grade type combination is selected so as not to exceed this range.

[0031] Thus, according to another aspect, a) two or more, possibly three or more, grades of PVOH, optionally in an amount ranging from 30 to 99% by weight; b) at least one cross-linking compound present in an amount of 0 or in the range of 0.1 to 20% by weight; c) at least one additional bioplastic, optionally present in an amount ranging from 0.1 to 50% by weight; and d) at least one additive in an amount ranging from 0.1 to 20% by weight; A composition comprising:

[0032] In some embodiments, the three or more PVOH grades are - PVOH grade type 1, characterized by one or more of the following: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; - PVOH grade type 2 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; - PVOH grade type 3 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; is selected from.

[0033] In some embodiments, the three or more PVOH grades are selected from PVOH Grade Type 1, which is characterized by one or more of the following: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) Molecular weight of 35–75 KDa.

[0034] In some embodiments, the three or more PVOH grades are selected from PVOH grade Type 2, characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) Molecular weight between 60 and 120 KDa.

[0035] In some embodiments, the three or more PVOH grades are selected from PVOH grade type 3, characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) Molecular weight of 22–35 KDa.

[0036] In some embodiments, the three or more PVOH grades are at least one PVOH grade type 1 characterized by one or more of the following: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; at least one PVOH grade type 2 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; at least one PVOH grade type 3 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; Includes:

[0037] In some embodiments, the three or more PVOH grades are - a single PVOH of grade type 1 characterized by one or more of the following: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; - a single PVOH of grade type 2 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; - a single PVOH of grade type 3 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; Includes:

[0038] In some embodiments, the composition comprises three PVOH grades: - a single PVOH of grade type 1 characterized by one or more of the following: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; - a single PVOH of grade type 2 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; - a single PVOH of grade type 3 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; Includes:

[0039] In some embodiments, the composition comprises three PVOH grades: - Single PVOH of grade type 1, characterized by: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; - Single PVOH of grade type 2, characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; - Single PVOH of grade type 3, characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; Includes:

[0040] In some embodiments, the composition comprises: (a) Three PVOH grades: - Single PVOH of grade type 1, characterized by: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; - Single PVOH of grade type 2, characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; - Single PVOH of grade type 3, characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; (b) at least one cross-linking compound; (c) optionally, at least one additional bioplastic; and (d) optionally, at least one additive; Includes:

[0041] In some embodiments, the composition comprises: (a) Three PVOH grades: - Single PVOH of grade type 1, characterized by: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; - Single PVOH of grade type 2, characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; - Single PVOH of grade type 3, characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; (b) at least one additional bioplastic; (c) at least one additive, and (d) at least one cross-linking compound; Includes:

[0042] In some embodiments, the crosslinking compound is a compound capable of associating or crosslinking with any of the PVOH grades present in the composition. The crosslinking compound is selected from polymers, copolymers, and non-polymeric materials, each of which has functional groups capable of associating with OH functional groups present on the PVOH backbone.

[0043] The cross-linking or association is usually through the formation of covalent bonds. In other instances, the association can be physical, i.e., in which case the polymer chains become entangled. In some embodiments, the association is through the formation of hydrogen bonds and / or ionic bonds. Regardless of the type of association, the cross-linking molecules are selected to provide an association that results in a desired physical-mechanical profile.

[0044] The functional groups of the crosslinking compound that allow it to associate with PVOH may be inherent functional groups of the compound, e.g., an oligomer or polymer, or may be functional groups grafted, associated, or added to the compound to impart crosslinking capability. In some embodiments, the crosslinking compound comprises functional groups selected from alcohol, epoxide, anhydride, carboxylic acid, amine, amide, glycidyl functional group, aldehyde functional group, ester, etc. The crosslinking compound may also be a polymer selected from ionomers, i.e., polymers having one or more functional groups capable of forming ionic groups. In some embodiments, the ionomer is a polyacid, optionally selected from poly(acrylic acid) (PAA), poly(methacrylic acid) (PMAA), etc.

[0045] In some embodiments, the crosslinking compound is a polymer grafted with an anhydride, such as maleic anhydride. In some embodiments, the polymer to which the maleic anhydride is grafted can be selected from polyethylene (PE), polylactic acid (PLA), polycaprolactone (PCL), polyhydroxybutyrate (PHB), poly(butylene adipate-co-terephthalate) (PBAT), etc. In some embodiments, the crosslinking compound is polyethylene-graft-maleic anhydride.

[0046] In some embodiments, the crosslinking compound is a polymer having carboxylic acid functionality, hi some embodiments, the polymer is selected from poly(ethylene-co-acrylic acid) (PE-co-AA), poly(ethylene-co-methacrylic acid) (PE-co-MAA), poly(lactide-block-acrylic acid) (PLA-block-AA), PVOH having carboxyl groups, carboxymethylcellulose (CMC), etc.

[0047] In some embodiments, the polymer is poly(ethylene-co-acrylic acid).

[0048] In some embodiments, the polymer is a polymer with glycidyl functionality.

[0049] In some embodiments, at least one cross-linking compound is a copolymer.

[0050] In some embodiments, the crosslinking compound is a small molecule crosslinking compound that is not a polymer, oligomer, or copolymer, and in such embodiments, the compound is typically selected from among aldehyde compounds, carboxylic acid compounds, amine compounds, halogen-substituted compounds, and other compounds that are reactive in the presence of or toward PVOH.

[0051] In some embodiments, the aldehyde compound may be selected from monoaldehydes and dialdehydes, hi some embodiments, the aldehyde is selected from formaldehyde, glutaraldehyde, glyoxal, malondialdehyde, succindialdehyde, phthalaldehyde, and the like.

[0052] In some embodiments, the carboxylic acid compound is selected from monocarboxylic acids, dicarboxylic acids, tricarboxylic acids, and their higher homologs. Alternatively, the carboxylic acids may be selected based on the number of carboxylate or basic groups they can form. Thus, similarly, the compounds may be selected from monobasic acids, dibasic acids, tribasic acids, and their higher homologs. In some embodiments, the carboxylic acid compound is selected from citric acid, boric acid, humic acid, phthalic acid, terephthalic acid, malic acid, sulfosuccinic acid, isophthalic acid, aconitic acid, fumaric acid, tartaric acid, and the like.

[0053] The additional bioplastics (or simply "bioplastics") used in accordance with the present invention are polymers that are different from the other polymeric components used in the compositions of the present invention, all of which are also substantially bioplastics. Additional bioplastics may represent natural polymers produced or derived from natural sources, such as cells of living organisms, plants, and other natural sources. Such polymers may be entirely natural or partially synthetic, i.e., derived from nature and chemically modified to structurally alter the natural polymer. Bioplastics used in accordance with the present invention may also represent biodegradable or compostable polymers that are partially or entirely derived from petrochemical sources.

[0054] In some embodiments, the additional bioplastic is selected from polypeptides and polysaccharides.

[0055] In some embodiments, the additional bioplastic is selected from an aliphatic or aromatic polyester, copolyester, or polyesteramide.

[0056] In some embodiments, the additional bioplastic is selected from poly(ethylene oxide) (PEO), poly(ethylene glycol) (PEG), polycaprolactone (PCL), polylactic acid (PLA), cellulose and cellulose derivatives, starch, thermoplastic starch (TPS), chitosan, polyhydroxyalkanoates (PHAs) such as polyhydroxybutyrate (PHB).

[0057] The cellulose derivatives are crystalline derivatives thereof or any other amorphous form of such materials. Non-limiting examples include nanocrystalline cellulose (NCC), microfibril cellulose, microcrystalline cellulose (MCC), bacterial cellulose (BC), hydroxypropylmethylcellulose (HPMC), hydroxypropylcellulose (HPC), hydroxyethylcellulose (HEC), and carboxymethylcellulose (CMC).

[0058] The at least one additive used in the composition of the present invention may be selected from inorganic additives, fillers, or reinforcing agents, and from low molecular weight additives (having a molecular weight of less than 3000 Da), each selected to improve various properties of the products formed from the composition of the present invention. Such additives may include processing aids, slip agents, light stabilizers, UV absorbers, flame retardants, antibacterial agents, antiviral agents, foaming agents, nucleating agents, antioxidants, antiblocking agents, antistatic agents, etc.

[0059] In some embodiments, the additive is a moisture absorbent and is optionally selected from CaO, CaCl, LiCl, NaCl, CaI, MgCl, TiO, CaCO, alumina silicate fillers, SiO, etc. In some embodiments, the additive is CaO.

[0060] In some embodiments, the additive is an inorganic salt containing a metallic or non-metallic element. In some embodiments, the inorganic salt is an inorganic salt of a metal selected from alkali metals and alkaline metals. In some embodiments, the inorganic salt is a salt of a transition metal.

[0061] Non-limiting examples of inorganic salts include halide salts of metals selected from Li, K, Ca, Na, Mg, Mn, Zn, and the like.

[0062] The inorganic salt can be a halide salt (wherein the halide atom is the anion to the metal cation). In some embodiments, the inorganic salt can be selected from LiCl, NaCl, CaCl, CaI, and MgCl. In some embodiments, the inorganic salt is CaCl.

[0063] In some embodiments, the composition comprises: (a) three or more PVOH grades selected from the following: at least one PVOH grade type 1 characterized by one or more of the following: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; at least one PVOH grade type 2 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; at least one PVOH grade type 3 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; (b) a crosslinked polymer, which is optionally poly(ethylene-co-acrylic acid); (c) bioplastics selected from poly(ethylene oxide) (PEO), poly(ethylene glycol) (PEG), polycaprolactone (PCL), polylactic acid (PLA), cellulose and cellulose derivatives, starch, thermoplastic starch (TPS), chitosan, polyhydroxyalkanoates (PHAs) such as polyhydroxybutyrate (PHB); (d) a salt selected from hygroscopic salts and halide salts, such as CaO and CaCl, respectively; Includes:

[0064] In some embodiments, the composition comprises: (a) three PVOH grades, which are: - a single PVOH of grade type 1 characterized by one or more of the following: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; - a single PVOH of grade type 2 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; - a single PVOH of grade type 3 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; (b) a crosslinked polymer, which is optionally poly(ethylene-co-acrylic acid); (c) bioplastics selected from poly(ethylene oxide) (PEO), poly(ethylene glycol) (PEG), polycaprolactone (PCL), polylactic acid (PLA), cellulose and cellulose derivatives, starch, thermoplastic starch (TPS), chitosan, polyhydroxyalkanoates (PHAs) such as polyhydroxybutyrate (PHB); (d) a salt selected from hygroscopic salts and halide salts, such as CaO and CaCl, respectively; Includes:

[0065] In some embodiments, the composition comprises: (a) three PVOH grades consisting of or consisting of: - a single PVOH of grade type 1 characterized by one or more of the following: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; - a single PVOH of grade type 2 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; - a single PVOH of grade type 3 characterized by one or more of the following: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; (b) a crosslinked polymer, which is optionally poly(ethylene-co-acrylic acid); (c) bioplastics selected from poly(ethylene oxide) (PEO), poly(ethylene glycol) (PEG), polycaprolactone (PCL), polylactic acid (PLA), cellulose and cellulose derivatives, starch, thermoplastic starch (TPS), chitosan, polyhydroxyalkanoates (PHAs) such as polyhydroxybutyrate (PHB); (d) a salt selected from hygroscopic salts and halide salts, such as CaO and CaCl, respectively; Includes:

[0066] In some embodiments, the composition comprises: (a) A single PVOH of grade type 1 characterized by: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of about 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa; (b) A single PVOH of grade type 2 characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of about 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa; (c) A single PVOH of grade type 3 characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa; (d) a crosslinked polymer which is optionally poly(ethylene-co-acrylic acid); (e) bioplastics selected from poly(ethylene oxide) (PEO), poly(ethylene glycol) (PEG), polycaprolactone (PCL), polylactic acid (PLA), cellulose and cellulose derivatives, starch, thermoplastic starch (TPS), chitosan, polyhydroxyalkanoates (PHAs) such as polyhydroxybutyrate (PHB); (f) a salt selected from hygroscopic salts and halide salts, such as CaO and CaCl, respectively; Includes:

[0067] As used herein, "PVOH grade" refers to different forms of poly(vinyl alcohol) (PVOH) that can be provided in the compositions of the present invention. As known in the art, PVOH is a highly hydrophilic, water-soluble polymer that can be obtained with different degrees of hydrolysis, hydroxylation, ethylene content, or polymerization, and thus molecular weight, and viscosity. Each of these variables determines the physical, chemical, and mechanical properties of the material, and thus the different grade types of PVOH material. Within the context of the invention disclosed herein, a grade is distinguished from other grades in at least one of (i) the degree of hydrolysis, (ii) the degree of polymerization as reflected in molecular weight, and (iii) viscosity.

[0068] The compositions of the present invention may contain a blend of PVOH grades or grade types. In other words, the compositions of the present invention contain two or more, or three or more, grades of PVOH. Three PVOH grade types may be used as stocks for producing the compositions and products of the present invention. Each of the different grade types, referred to herein as Grade Type 1, Grade Type 2, and Grade Type 3, constitutes a different group of PVOH materials defined by the indicated properties and, therefore, each may be used individually to formulate the compositions of the present invention. Thus, a PVOH grade blend containing at least two or more PVOH grades may be derived from a Type 1 PVOH grade, a Type 2 PVOH grade, or a Type 3 PVOH grade, or a mixture of various PVOH grade types. For example, if a blend contains three different PVOH grades, all three may be selected from the same grade type, e.g., Grade Type 1, provided that each of the three differs in at least one of (i) degree of hydrolysis, (ii) degree of polymerization or molecular weight, and (iii) viscosity. Similarly, the three grades may be selected from different grade types.

[0069] The main raw material used in the production of polyvinyl alcohol is vinyl acetate monomer. PVOH is produced by partial or complete hydrolysis after the polymerization of vinyl acetate. The hydrolysis process is based on the replacement of some or all of the ester groups in vinyl acetate with hydroxyl groups through a saponification process. The "degree of hydrolysis" is determined at the point at which the saponification reaction is stopped. PVOH can therefore be classified as partially hydrolyzed or fully hydrolyzed. PVOH grades used in accordance with the present invention are partially hydrolyzed, while some are fully hydrolyzed. Typically, the degree of hydrolysis is in the range of 86-99% (mol%). In other words, 86-99% of the acetate groups are saponified and converted to hydroxyl groups, with 1-14% remaining acetate groups. Note that 99% hydrolysis is sometimes considered complete hydrolysis.

[0070] The "degree of polymerization" of PVOH is generally reflected in the molecular weight of the material, and can be expressed as the viscosity average degree of polymerization obtained from the viscosity in water.

[0071] As described herein, each grade of PVOH is selected to have a degree of hydrolysis in the range of 86-99 mol % and a degree of polymerization in the range of 500-3000. In some embodiments, the degree of polymerization is in the range of 500-2600.

[0072] The present invention also provides formulations according to the invention, as listed in Table 2. TIFF0007818088000002.tif128170

[0073] Accordingly, the present invention further provides one or more of the following compositions: 1. A composition comprising 37% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, 20% by weight of PVOH grade type 1, 0.1% by weight of a crosslinker such as PAA, 0.4% by weight of a bioplastic such as PEO, and 13% by weight of glycerol as a plasticizer; 2. A composition comprising 35% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, 20% by weight of PVOH grade type 1, 0.1% by weight of a crosslinker such as PAA, 0.4% by weight of a bioplastic such as PEO, and 15% by weight of glycerol as a plasticizer; 3. A composition comprising 30% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, 20% by weight of PVOH grade type 1, 0.1% by weight of a crosslinker such as PAA, 0.4% by weight of a bioplastic such as PEO, and 19% by weight of glycerol as a plasticizer; 4. A composition comprising 79% by weight of PVOH grade type 3, 10% by weight of PVOH grade type 2, and 11% by weight of glycerol as plasticizer; 5. A composition comprising 70% by weight of PVOH grade type 3, 20% by weight of PVOH grade type 2, and 10% by weight of glycerol as plasticizer; 6. A composition comprising 61% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, and 9% by weight of glycerol as plasticizer; 7. A composition comprising 57% by weight of PVOH grade type 3, 10% by weight of PVOH grade type 2, 20% by weight of PVOH grade type 1, 0.1% by weight of a crosslinker such as PAA, 0.4% by weight of a bioplastic such as PEO, and 13% by weight of glycerol as a plasticizer; 8. A composition comprising 47% by weight of PVOH grade type 3, 20% by weight of PVOH grade type 2, 20% by weight of PVOH grade type 1, 0.1% by weight of a crosslinker such as PAA, 0.4% by weight of a bioplastic such as PEO, and 13% by weight of glycerol as a plasticizer; 9. A composition comprising 37% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, 20% by weight of PVOH grade type 1, 0.1% by weight of a crosslinker such as PAA, 0.4% by weight of a bioplastic such as PEO, and 13% by weight of glycerol as a plasticizer; 10. A composition comprising 61% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, and 9% by weight of glycerol as plasticizer; 11. A composition comprising 57% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, and 13% by weight of glycerol as plasticizer; 12. A composition comprising 53% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, and 18% by weight of glycerol as plasticizer; 13. A composition comprising 40% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, 20% by weight of PVOH grade type 1, and 10% by weight of glycerol as plasticizer; 14. A composition comprising 36% by weight of PVOH grade type 3, 30% by weight of PVOH grade type 2, 20% by weight of PVOH grade type 1, and 14% by weight of glycerol as a plasticizer.

[0074] The compositions of the present invention can be used as resins in the polymer industry. The compositions can be converted into stock forms containing a preselected set of materials in amounts and ratios appropriate for the production of a particular polymer product. One such stock material is pellets or solid particulate materials (such as beads) that can be used directly in the production of a final polymer product, such as a polymer film or sheet. Pellets or particulate solid forms can be produced by compounding the compositions of the present invention under preselected conditions. Through the compounding process, the composition or resin is converted into a form with properties that make it more effective, efficient, and uniform, ready for further processing, including processes such as molding or extrusion. Pellets can have any shape, but are typically small, flat-sided rods or cylinders, such as cubes or rectangular prisms. Pellets are formed from a homogeneous mixture of the compositions of the present invention processed as disclosed herein.

[0075] Thus, the present invention further provides pellets or solid materials (eg, beads) formed from or including the compositions of the present invention.

[0076] In some embodiments, the pellets obtained by compounding the compositions of the present invention comprise crosslinked PVOH, which in some embodiments includes crosslinking between PVOH grades, between PVOH and glycerol, or between PVOH, glycerol, and other components present in the composition.

[0077] In some embodiments, the formulation is prepared by heat treating the composition of the present invention to - Blends of PVOH grades with each other and with additives, - plasticization of PVOH by forming hydrogen bonds between PVOH and glycerol, - cross-linking between PVOH grades and / or between PVOH grades and glycerol, and / or - Volatilization of water or other components that are volatile under these conditions, This includes causing one or more of the following:

[0078] The present invention further provides a method for producing pellets from the compositions of the present invention, which method comprises compounding the composition under conditions selected to convert the composition into a solid particulate material.

[0079] In some embodiments, the conditions include converting the composition to a molten state and causing evaporation or partial evaporation of volatile materials. Thus, compounding can be carried out by extrusion, for example, in an extruder, such as a twin-screw extruder.

[0080] In some embodiments, the twin screw extruder is a co-rotating extruder or a counter-rotating extruder.

[0081] In some embodiments, compounding involves the use of a kneader and / or mixer.

[0082] In some embodiments, compounding can be accomplished by heating the composition and subsequently exposing the melt to a rapid reduction in pressure. In some embodiments, compounding can be carried out in a twin-screw extruder equipped with a suitable devolatilizing system to remove unreacted monomers, solvent, water, dissolved gases, or other undesirable volatile materials from the polymer melt.

[0083] The pellets or solid particulate material formed by incorporating the composition of the present invention may be used to manufacture polymeric objects, e.g., polymeric films or sheets, by further processing the pellets or solid particulate material, for example, by molding or extrusion. Thus, in another aspect of the present invention, there is provided the use of the composition of the present invention to manufacture polymeric articles, such as polymeric films or polymeric sheets.

[0084] The present invention further provides a method for producing a polymeric article, such as a film or sheet, which method comprises converting a formulated form of the composition of the present invention into a polymeric article, for example by molding or extrusion.

[0085] In some embodiments, the method comprises extruding a compounded form of the composition of the present invention.

[0086] In some embodiments, the compounded form of the composition is a pelletized form.

[0087] In some embodiments, the pelletized form is obtained by compounding as disclosed herein. In some embodiments, compounding is accomplished by converting the composition to a molten state and then causing the evaporation or partial evaporation of volatile materials. Compounding can be accomplished by extrusion, for example, in an extruder, such as a twin-screw extruder. In some embodiments, the twin-screw extruder is a co-rotating or counter-rotating extruder. In some embodiments, compounding involves the use of a kneader and / or mixer. In some embodiments, compounding can be accomplished by heating the composition and subsequently subjecting the melt to rapid decompression. In some embodiments, compounding can be accomplished in a twin-screw extruder equipped with a suitable devolatilization system to remove unreacted monomers, solvent, water, dissolved gases, or other undesirable volatile materials from the polymer melt.

[0088] In some embodiments, a method for making a polymeric product, such as a film or sheet, includes compounding a composition of the present invention into a pellet form and converting the pellet form into a polymeric product, for example, by molding or extrusion.

[0089] In some embodiments, the method comprises: - providing a composition according to the invention, - compounding said composition into pellets; and - converting the pellets into polymer products; Includes:

[0090] Conversion of the compounded form, e.g., pellets, into a polymer product may be achieved by molding or extrusion. Depending on the size and shape of the polymer product, appropriate techniques may be utilized. If the product is a film or sheet, conversion may include blown film extrusion or cast film extrusion.

[0091] In some embodiments, films or sheets are produced by blown film extrusion. In this process, the compounded material of the present invention, often in the form of pellets or beads, is introduced into a hopper and fed into a heated barrel equipped with a screw. The pellets are gradually heated to melt the polymer, and the molten material is then extruded through a die. Various dies can be used, one such die being an annular or ring-shaped die. The molten polymer enters the die head, and air is injected through a hole in the center of the die to radially expand the polymer into a thin tube many times the extrusion diameter. The thickness and width of the film can be adjusted to meet the desired film profile. After extrusion, the hot tube film is cooled and taken up, for example, by nip rollers. As the film cools, it flattens and is transported for further processing.

[0092] The blown extrusion process can be used to manufacture a wide variety of products, from simple monolayer films to complex multilayer structures used, for example, in food packaging.

[0093] Multilayer films may also be produced by blown coextrusion, which combines two or more molten polymeric materials.

[0094] In some embodiments, the film or sheet is produced by a cast film extrusion process, where, unlike a blown film extrusion process, the molten polymer is fed through a flat die system to assume its final flat film shape. In the case of coextrusion, the die system may comprise a die and a feedblock, while in the case of monolayer extrusion, a flat die may be used.

[0095] The orientation of the polymer film or sheet can be established or modified by tenter frame orientation, double bubble orientation, or machine direction orientation.

[0096] Once formed, the film can be further modified by roll slitting, coating or printing, and physical vapor deposition to produce a metallized film. The film may also be subjected to corona or plasma treatment, and a release agent may be applied if desired.

[0097] In some embodiments, the films may be thermoformed, stretched, compression molded, and laminated.

[0098] In some embodiments, the extruded film is oriented while being stretched.

[0099] The oriented or shrinkable film of the present invention may be of any thickness depending on the desired end use. For some applications, where the film and / or shrinkable film is intended to be printed with ink for applications such as labels that can be adhered to a substrate such as paper, the film thickness may be thinner than the shrinkable protective film. In some embodiments, the film has a thickness of 10 microns to 500 microns, or 25 microns to 500 microns, or 50 microns to 500 microns, or 100 microns to 500 microns, 150 microns to 500 microns, 200 microns to 500 microns, 250 microns to 500 microns, 300 microns to 500 microns, 350 microns to 500 microns, 400 microns to 500 microns, or 450 microns to 500 microns.

[0100] In some embodiments, films may be provided in thicknesses of 10 microns to 100 microns, 10 microns to 90 microns, 10 microns to 80 microns, 10 microns to 70 microns, 10 microns to 60 microns, 10 microns to 50 microns, 10 microns to 40 microns, 10 microns to 30 microns, 10 microns to 20 microns, 20 microns to 100 microns, 30 microns to 100 microns, 40 microns to 100 microns, 50 microns to 100 microns, 60 microns to 100 microns, 70 microns to 100 microns, 80 microns to 100 microns, 90 microns to 100 microns, 30 microns to 90 microns, 30 microns to 80 microns, 30 microns to 70 microns, 30 microns to 60 microns, or 30 microns to 50 microns.

[0101] In some embodiments, the film may be provided in a thickness of 10 microns to 200 microns, 10 microns to 300 microns, or 10 microns to 400 microns.

[0102] The polymeric films of the present invention may be used in a wide variety of applications including packaging, plastic bags, labels, shrink labels, electronic manufacturing, photographic film, film stock for films, and the like.

[0103] The combination of the improved shrink properties discussed herein and the improved polymer stability with controlled biodegradability discussed below offers new commercial opportunities, including recyclability and easy, non-polluting decomposition of shrink films applied to containers, plastic bottles, glass bottles, packaging, batteries, hot content containers, and / or industrial articles.

[0104] As is commonly known in the art, some polymer films may be oriented, stretched, and then quenched so that the polymer chains exhibit a memory effect. The strain generated in the film is released by raising the temperature of the film, causing the film to shrink. The shrink property is built into the film during its manufacture by stretching the film under controlled temperatures to induce molecular orientation. After cooling, the film maintains its stretched state, but when heated, it returns to its original dimensions. When heated around a package, the film shrinks onto the surface of the package, with the package acting as a mold in this case. Shrinkable films provide good protection and, in some cases, excellent transparency.

[0105] The ability of a polymer to undergo orientation and the degree of shrinkage, among other parameters, depend on polymer properties such as chemical nature, level of hydrogen bonding, molecular weight, molecular weight distribution, and long chain branching. For example, broader molecular weight distribution and higher molecular weight lead to increased shrinkage. In addition, the degree of crystallinity, crystalline morphology, and crystallization rate also affect the ability of a polymer to undergo orientation and shrinkage.

[0106] It is known that the degree of crystallinity of PVOH is affected by the degree of hydrolysis and polymerization. A higher degree of hydrolysis can sometimes lead to an increased level of hydrogen bonding and, at the expense of poor melt processability, improved shrinkage and shrink force. PVOH with a lower degree of hydrolysis results in better melt processability. Therefore, blending PVOH with different molecular weights and degrees of hydrolysis makes it possible to balance stretchability, shrinkability, and melt processability. Combined with an optimal film manufacturing process, films with shrinkage rates of over 70% were produced, making them suitable for shrink wrapping.

[0107] The shrink films of the present invention can be used to bundle, organize, or overwrap products for unitization, display aesthetics, and / or tamper-evident properties. A very widely used product is shrink wrap, which can be used to package products.

[0108] Accordingly, the present invention further provides a polymeric film prepared as disclosed herein and having heat shrinkability.

[0109] Also provided are polymeric films formed from compositions or combinations of PVOH grades according to the present invention that exhibit heat shrinkability.

[0110] Also provided is a shrinkable polymeric film according to the present invention for use in making shrinkable articles.

[0111] Also provided is a shrink wrap formed from the inventive formulations disclosed herein.

[0112] Additionally, there is provided a biodegradable (ie, biodegradable in water, soil, etc.) shrinkable polymer or film or packaging material in accordance with the present invention.

[0113] As used herein with respect to the films and shrinkable films of the present invention, the term "film" includes both films and sheets and embraces its meaning as generally accepted in the art. This term includes monolayer and multilayer films. "Shrinkable film" refers to a shrinkable film in which shrinkage is induced by exposure to heat. While the term "film" can refer to a flat, continuous sheet of material, the term shrinkable film equally refers to sleeves and labels, including wraparound labels, sleeve labels, shrinkable sleeve labels, and shrinkable wrap labels.

[0114] The shrinkable films of the present invention may have a shrink initiation temperature, i.e., the temperature at which shrinkage begins, of 50 to 90° C., 55 to 85° C., or 60 to 75° C. In some embodiments, the shrink initiation temperature is greater than 100° C.

[0115] In some embodiments, the shrinkage initiation temperature is 100 to 200°C, or 150 to 200°C.

[0116] The shrinkage may be gradual or not. In some embodiments, the shrinkable films of the present invention may have a shrinkage percentage in the direction of extrusion, i.e., machine direction or MD, of at least 70%. In some embodiments, the shrinkable films of the present invention exhibit MD shrinkage of 20-85%, or 20-82%, or 30-85%, or uniquely greater than 70%.

[0117] The films and shrinkable films of the present invention are hydrodegradable or generally biodegradable. In other words, the films of the present invention decompose within a range of several minutes to several days upon contact with water. Non-limiting examples of shrinkable films of the present invention are shown in Table 3. TIFF0007818088000003.tif135170

[0118] The present invention further provides a composition comprising glycerol in an amount of 19 wt%, PEO in an amount of 0.4 wt%, PAA in an amount of 0.1 wt%, Grade Type 1 PVOH in an amount of 20 wt%, Grade Type 2 PVOH in an amount of 30%, and Grade 3 PVOH in an amount of 30%.

[0119] The present invention further provides a method for producing pellets from a composition comprising glycerol in an amount of 19 wt%, PEO in an amount of 0.4 wt%, PAA in an amount of 0.1 wt%, Grade Type 1 PVOH in an amount of 20 wt%, Grade Type 2 PVOH in an amount of 30%, and Grade 3 PVOH in an amount of 30%, the method comprising blending the composition under conditions selected to convert the composition into a solid particulate material.

[0120] In some embodiments, compounding includes mixing the composition in a high-speed mixer at 100°C for 1 hour, feeding the mixture into a co-rotating twin-screw extruder equipped with a devolatilizing system, and extruding it through a round die at 190-220°C.

[0121] In some embodiments, extrusion parameters such as screw design, speed, and feed rate were optimized for optimal residence time and mixing inside the extruder.

[0122] The exiting polymer strands were passed through an air cooling system and a pelletizer.

[0123] In some embodiments, the pellets are processed into a thin film using blown film extrusion.

[0124] In some embodiments, film orientation is achieved during film manufacturing, with the desired orientation and associated shrinkage characteristics being controlled by the blow-up and draw-down ratios. DETAILED DESCRIPTION OF THE INVENTION

[0125] All components were mixed and extruded through a round die at 190-220°C using a co-rotating twin-screw extruder equipped with a devolatilization system. Extrusion parameters, such as screw design, speed, and feed rate, were optimized for optimal residence time and mixing within the extruder. The exiting polymer strands were passed through an air-cooling system and a pelletizer. The resulting pellets were further processed into thin films using blown film extrusion. Film orientation was achieved during film production, with the desired orientation and associated shrinkage characteristics controlled by the blow-up and draw-down ratios.

[0126] To apply the film as a shrink wrap, the film is wrapped around the item to be shrink wrapped, and both the film and the item are heated to a particular temperature until the film shrinks around the item.

[0127] Film characteristics The properties of the resulting film depend on the parameters used in film production, i.e., blow-up and draw-down ratios. Typically, the films are strong and flexible, and are fully comparable to conventional polyethylene shrink films routinely used in shrink applications. Some typical values ​​for 30-60 μm films can be found in Table 4 below. TIFF0007818088000004.tif68170

[0128] Water decomposability is characterized by the time required to dissolve a film of a given thickness at a given temperature under agitation.

Claims

1. 1. A polymer composition for producing a biodegradable shrinkable film, the polymer composition comprising: a) three or more PVOH grade types in an amount ranging from 30 to 99 wt. %; b) at least one cross-linking compound, in an amount of 0 or in the range of 0.1 to 20% by weight; c) at least one additional bioplastic in an amount ranging from 0.1 to 50% by weight; and d) at least one additive in an amount ranging from 0.1 to 20% by weight Including, The three or more PVOH grade types are - Single PVOH of grade type 1, characterized by: (i) a degree of hydrolysis of 98-99%; (ii) a degree of polymerization of 800 to 1700, and (iii) a molecular weight of 35 to 75 KDa - Single PVOH of grade type 2, characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 1400 to 2600, and (iii) a molecular weight of 60 to 120 KDa - Single PVOH grade type 3 characterized by: (i) a degree of hydrolysis of 86 to 89%; (ii) a degree of polymerization of 500 to 800, and (iii) a molecular weight of 22 to 35 KDa A polymer composition comprising:

2. 10. The polymer composition of claim 1, comprising crosslinking compounds selected from polymers, copolymers, and non-polymeric materials, each having functional groups capable of associating with OH functional groups present in the PVOH.

3. 3. The polymer composition of claim 2, wherein the crosslinking compound comprises a functional group selected from alcohol, epoxide, anhydride, carboxylic acid, amine, amide, glycidyl functional group, aldehyde functional group, and ester.

4. 3. The polymer composition of claim 2, wherein the crosslinking compound is a polymer selected from among ionomers.

5. 5. The polymer composition of claim 4, wherein the ionomer is a polyacid selected from poly(acrylic acid) (PAA) and poly(methacrylic acid) (PMAA).

6. The polymer composition of claim 2 , wherein the crosslinking compound is an anhydride-grafted polymer.

7. 7. The polymer composition of claim 6, wherein the anhydride is maleic anhydride.

8. 8. The polymer composition of claim 7, wherein the polymer grafted with maleic anhydride is selected from polyethylene (PE), polylactic acid (PLA), polycaprolactone (PCL), polyhydroxybutyrate (PHB), and poly(butylene adipate-co-terephthalate) (PBAT).

9. The polymer composition of claim 6, wherein the cross-linking compound is polyethylene-graft-maleic anhydride.

10. The polymer composition of claim 2 , wherein the cross-linking compound is a polymer having carboxylic acid functional groups.

11. 11. The polymer composition of claim 10, wherein the polymer is selected from poly(ethylene-co-acrylic acid) (PE-co-AA), poly(ethylene-co-methacrylic acid) (PE-co-MAA), poly(lactide-block-acrylic acid) (PLA-block-AA), PVOH having carboxyl groups, and carboxymethyl cellulose (CMC).

12. The polymer composition of claim 11, wherein the polymer is poly(ethylene-co-acrylic acid).

13. The polymer composition of claim 2 , wherein the polymer is a polymer having glycidyl functional groups.

14. The polymer composition of claim 2 , wherein the crosslinking compound is a copolymer.

15. The polymer composition of claim 2 , wherein the crosslinking compound is a small molecule crosslinking compound that is not a polymer, oligomer, or copolymer.

16. 16. The polymer composition of claim 15, wherein the crosslinking compound is selected from aldehyde-based compounds, carboxylic acid compounds, amine compounds, and halogen-substituted compounds.

17. 17. The polymer composition of claim 16, wherein the aldehyde compound is selected from monoaldehydes and dialdehydes.

18. 18. The polymer composition of claim 17, wherein the aldehyde-based compound is selected from formaldehyde, glutaraldehyde, glyoxal, malondialdehyde, succindialdehyde, and phthalaldehyde.

19. 17. The polymer composition of claim 16, wherein the carboxylic acid compound is selected from monocarboxylic acids, dicarboxylic acids, tricarboxylic acids, and their higher homologues.

20. 20. The polymer composition of claim 19, wherein the carboxylic acid compound is selected from citric acid, boric acid, humic acid, phthalic acid, terephthalic acid, malic acid, sulfosuccinic acid, isophthalic acid, aconitic acid, fumaric acid, and tartaric acid.

21. The polymer composition of claim 1 , wherein the additional bioplastic is selected from polypeptides and polysaccharides.

22. 22. The polymer composition of claim 21, wherein the additional bioplastic is selected from an aliphatic or aromatic polyester, copolyester, or polyesteramide.

23. 23. The polymer composition of claim 22, wherein the additional bioplastic is selected from poly(ethylene oxide) (PEO), poly(ethylene glycol) (PEG), polycaprolactone (PCL), polylactic acid (PLA), cellulose and cellulose derivatives, starch, thermoplastic starch (TPS), chitosan, polyhydroxyalkanoates (PHA), and polyhydroxybutyrate (PHB).

24. 10. The polymer composition of claim 1, wherein the at least one additive is selected from inorganic additives, fillers, reinforcing agents, and low molecular weight additives having a molecular weight of less than 3000 Da.

25. 25. The polymer composition of claim 24, wherein the at least one additive is selected from processing aids, slip agents, light stabilizers, UV absorbers, flame retardants, antibacterial agents, antiviral agents, foaming agents, nucleating agents, antioxidants, antiblocking agents, and antistatic agents.

26. The additive is a moisture absorbent, and may contain, as desired, CaO, CaCl ２ , LiCl, NaCl, CaI ２ , MgCl ２ , TiO ２ , CaCO ３ , alumina silicate filler, SiO ２ 26. The polymer composition of claim 25, wherein the polymer composition is selected from:

27. 27. The polymer composition of claim 26, wherein the additive is CaO.

28. (b) a crosslinked polymer, which is optionally poly(ethylene-co-acrylic acid); (c) bioplastics selected from poly(ethylene oxide) (PEO), poly(ethylene glycol) (PEG), polycaprolactone (PCL), polylactic acid (PLA), cellulose and cellulose derivatives, starch, thermoplastic starch (TPS), chitosan, polyhydroxyalkanoates (PHA), and polyhydroxybutyrate (PHB); (d) a salt selected from hygroscopic salts and halide salts; 10. The polymer composition of claim 1, comprising:

29. 10. The polymer composition of claim 1 for use in compounding said polymer composition to make pellets.

30. A pellet or solid material formed from the polymer composition of claim 1.

31. 31. The pellet of claim 30 formed by compounding the polymer composition.

32. The compounding step comprises heat treating the polymer composition to - blending of three or more of said PVOH grade types; - plasticization of the PVOH to form hydrogen bonds between said PVOH and at least one plasticizer; - crosslinking between said PVOH grade types and / or between said PVOH grade types and said at least one plasticizer, and / or - Volatilization of water or other low boiling components, 32. The pellet of claim 31, comprising causing one or more of:

33. 10. A method for producing pellets from the polymer composition of claim 1, said method comprising compounding said polymer composition under conditions selected to convert said polymer composition into a solid particulate material.

34. 34. The method of claim 33, wherein the conditions include converting the polymer composition to a molten state and further causing evaporation or partial evaporation of volatile materials.

35. 35. The method of claim 34, carried out by extrusion, optionally in a twin screw extruder.

36. 36. The method of claim 35, wherein the twin screw extruder is a co-rotating extruder or a counter-rotating extruder.

37. 35. The method of claim 34, wherein the compounding comprises the use of a kneader and / or a mixer.

38. 10. Use of the polymer composition according to claim 1 for producing a polymer product.

39. 10. A method for producing a polymeric film or sheet, comprising converting a formulated form of the polymeric composition of claim 1 into said polymeric film or sheet.

40. 40. The method of claim 39, comprising extruding a compounded form of the polymer composition.

41. 41. The method of claim 40, wherein the compounded form is a pelletized form.

42. 42. The method of claim 41, wherein the pelletized form is obtained by the method of claim 33.

43. 40. The method of claim 39, comprising compounding the polymer composition into pellet form and converting the pellet form into the polymer film or sheet by extrusion.

44. - providing said polymer composition, - compounding said polymer composition into pellets; and - converting said pellets into said polymer film or sheet by blown film extrusion; 40. The method of claim 39, comprising:

45. 40. The method of claim 39, wherein the polymeric film is thermoformed, stretched, compression molded, or laminated.

46. 46. ​​The method of claim 45, wherein the extruded polymer film is oriented while being stretched.

47. A shrinkable film formed from the polymer composition of claim 1.

48. 48. The shrinkable film of claim 47 formed by the method of claim 39.

49. 48. The shrinkable film of claim 47 for use in packaging, plastic bags, labels, shrink labels, electronic manufacturing, photographic film, or film stock for film.

50. 48. The shrinkable film of claim 47, which exhibits heat shrinkability.

51. 48. The shrinkable film of claim 47 for use in making a shrinkable article.

52. 48. The shrinkable film of claim 47, which is biodegradable.

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