LIQUID ADDITIVE COMPOSITION

Abstract

A liquid additive composition containing a fluoropolymer; an organophosphite antioxidant; a sterically hindered phenol antioxidant; and one or more hydrocarbon polymer dispersants provided improved processing and product appearance in film applications, extrusion blow molding and as a masterbatch enhancer.

Claims

1. A liquid additive composition comprising: a fluoropolymer; an organophosphite antioxidant; a sterically hindered phenol antioxidant; and one or more hydrocarbon polymer dispersants.

2. The liquid additive composition according to claim 1, wherein the liquid additive composition has a viscosity in a range of 3000 to 20,000 centipoise.

3. The liquid additive composition according to claim 1, wherein the fluoropolymer is present in an amount of 10 to 25 wt %.

4. The liquid additive composition according to claim 1, wherein the organophosphite antioxidant is present in an amount of 15 to 35 wt %.

5. The liquid additive composition according to claim 1, wherein the sterically hindered phenol antioxidant is present in an amount of 0.5 to 10 wt %.

6. The liquid additive composition according to any claim 1, wherein the one or more hydrocarbon polymer dispersants are present in an amount of 30 to 75 wt %.

7. The liquid additive composition according to claim 1, wherein the fluoropolymer is a polyvinylidene fluoride.

8. The liquid additive composition according to claim 1, further comprising an additional antioxidant.

9. The liquid additive composition according to claim 1, wherein the one or more hydrocarbon polymer dispersants are polymerized C4-olefins.

10. The liquid additive composition according to claim 1, further comprising a polymeric dispersant that is not a polymerized C4-olefin.

11. The liquid additive composition according to claim 1, further comprising a matting agent.

12. (canceled)

13. The liquid additive composition according to claim 1, further comprising a thixotropic agent.

14. (canceled)

15. The liquid additive composition according to claim 1, comprising: a fluoropolymer; an organophosphite; a sterically hindered phenol; two different polymerized C4-olefins; a polymeric dispersant that is not a polymerized C4-olefin; a micronized polyethylene or polyethylene-containing wax; and silica.

16. The liquid additive composition according to claim 1, consisting of: a fluoropolymer; an organophosphite; a sterically hindered phenol; two different polymerized C4-olefins; a polymeric dispersant that is not a polymerized C4-olefin; a micronized polyethylene or polyethylene-containing wax; and silica.

17. An article comprising the liquid additive composition according to claim 1.

18. A film comprising the liquid additive composition according to claim 1.

19. (canceled)

20. An extruded blow molded article comprising the liquid additive composition according to claim 1.

21. A masterbatch comprising the liquid additive composition according to claim 1.

22. (canceled)

23. A process for improving the surface appearance of a film, comprising adding to the film or a precursor to the film the liquid additive composition according to claim 1.

24. A method of preparing a film that includes a step of adding the liquid additive composition according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0070] The following figures are merely representative of particular embodiments of the present invention and are not intended to otherwise limit the scope of the invention as described herein.

[0071] FIG. 1 illustrates the transmittance results for LLDPE films containing varying amounts of exemplary additive compositions of the invention.

[0072] FIG. 2 illustrates the difference in the improvement in clarity in a LLDPE film containing an exemplary composition of the invention where Kynar Flex? 5301 is the polyvinylidene fluoride component and where the composition is present at 0.015% LDR and at 1% LDR.

[0073] FIG. 3 illustrates the difference in the improvement in clarity in a LLDPE film containing an exemplary composition of the invention where Kynar Flex? 3121 is the polyvinylidene fluoride component and where the composition present at 0.015% LDR and at 1% LDR.

DETAILED DESCRIPTION OF THE INVENTION

[0074] The liquid additive composition of the invention imparts processing and appearance benefits in film applications. In an exemplary embodiment, the fluoropolymer component of the liquid additive composition is blended with a suitable resin to produce various film applications. The objectives for preparing articles (e.g., films) containing the liquid additive compositions include minimization of the amount of the liquid additive compositions required for the desired film characteristics in combination with lower processing temperatures and faster processing time which improves both the efficiency and productivity of the process for preparation of the additive-containing articles, and also results in reduced energy use and scrap generation. The use of smaller lot sizes also added to production flexibility.

[0075] The liquid additive composition of the invention may be in the form of a solution, a colloid or a suspension, where the form is typically temperature dependent.

[0076] In an exemplary embodiment, the desirable visual properties of a film in which the liquid additive composition of the present invention has been incorporated include improved clarity and an enhanced finished surface on the final article.

[0077] In an exemplary embodiment, the process benefits of a film in which the liquid additive composition of the present application has been incorporated include reduced or eliminated die build-up, increased throughput, uninterrupted film line processing, reduced degradation due to lower processing temperatures, shortened color change transitions and reduction of film friction (slip).

[0078] The described benefits associated with use of the additive composition of the present invention are likely due to the fact that the additive composition has an affinity to metal which allows facile coating of the processing equipment and die heads. This attribute allows for the creation of a low surface energy coating inside the processing equipment which facilitates the passage of masterbatch material through the equipment, which minimizes or eliminates undesirable blemishes (e.g., sharkskin) in the film, adds slip properties, increases throughput, reduces processing temperatures and lowers torque and psi.

[0079] Fluoropolymer Component

[0080] Polyvinylidene fluoride (PVDF) is a preferred fluoropolymer of the liquid additive composition of the present invention but other suitable fluoropolymers include polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE) and poly(vinyl fluoride) (PVF). In an exemplary embodiment, the fluoropolymer component is present in the liquid additive composition in an amount of 12 to 22 wt %, such as 13 to 21%, such as 14 to 21%, such at 15 to 20 wt %, such as 15 to 18 wt %. Preferred polyvinylidenes include Kynar Flex? 5300, Kynar Flex? 5301, Kynar Flex? 3121-50 and Kynar Flex? 2821.

[0081] Organophosphite Component

[0082] The organophosphite component of the liquid additive composition of the present invention acts as a process stabilizer and protects polymers from molecular weight changes and from thermooxidative degradation by decomposing hydroperoxides to form non-radical, non-reactive products. Irgafos? 126 and Irgafos? 168 are preferred organophosphites and are present in the liquid additive composition in an amount of 15 to 35 wt %, such as 17 to 35 wt %, such as 19 to 33 wt %, such as 20 to 30 wt %, such as 20 to 25 wt %.

[0083] Sterically Hindered Phenol Component

[0084] The sterically hindered phenol component of the liquid additive composition of the present invention chiefly acts as a non-discoloring stabilizer against protection against thermooxidative degradation. Preferred sterically hindered phenols include Irganox? 1010, Irganox? 1035, Irganox? 1076, Irganox? 1098, Irganox? 1135, Irganox? 1330, Irganox? 1425, Irganox? 1520 L, Irganox? 1726, Irganox? 245, Irganox? 245 DW, Irganox? 3114, Irganox? 565, Rianox (Thanox) 1076, Rianox (Thanox) 1098, Rianox (Thanox) 1790 and Rianox (Thanox) 3114. The sterically hindered phenol is present in the liquid additive composition in an amount of 0.5 to 10 wt %, such as 1 to 10 wt %, such as 2 to 8 wt %, such as 3 to 7 wt %, such as 4 to 6 wt %.

[0085] Hydrocarbon Polymer Component

[0086] Polymerized C4-olefins (such as polybutene) are a preferred hydrocarbon component of the liquid additive composition of the present invention but other suitable hydrocarbon polymers include copolymers of ethylene and propylene. In a particular embodiment, the polybutene is one or more of Indopol? L-2, Indopol? L-3, Indopol? L-6, Indopol? L-8, Indopol? L-14, Indopol? H-7, Indopol? H-8, Indopol? H-15, Indopol? H-25, Indopol? H-50, Indopol? H-100, Indopol? H-300 and Indopol? H-1200. The hydrocarbon polymer is present in the liquid additive composition in an amount of 0.5 to 10 wt %, such as 1 to 10 wt %, such as 2 to 8 wt %, such as 3 to 7 wt %, such as 4 to 6 wt %.

[0087] Polymeric Dispersant Component

[0088] The polymeric dispersant component that is present in various embodiments of the liquid additive composition of the invention aids in wetting particles present in the composition, reduces particle size and/or stabilizes the particles. Preferred polymeric dispersants include Solplus? K240, Solplus? K241, Solplus? K251, Solplus? DP310, Solplus? D320, Solplus? D330 and Solplus? DP700, but polyhydroxystearic acid dispersants and polyolefin amidealkeneamine dispersants are also suitable. The polymeric dispersant is present in the liquid additive composition in an amount of 0.1 to 5 wt %, such as 0.3 to 5 wt %, such as 0.5 to 5 wt %, such as 0.5 to 3 wt %, such as 0.5 to 2 wt %, such as 1 to 3 wt %.

[0089] Micronized Wax Component

[0090] Micronized waxes are most commonly a linear synthetic paraffin with a carbon number greater than 30 and provide improve anti-slip and abrasion resistance properties and matting. The preferred micronized wax component that is present in various embodiments of the liquid additive composition of the invention is a polyethylene or polyethylene-containing wax, but other suitable micronized waxes include Carnuba, ethylene bistearamide and polypropylene micronized waxes. Preferred micronized polyethylene or polythethylene-containing waxes include Ceridust? 3715, Ceridust? 3716 TP, Ceridust? 3620, Ceridust? 5551 and Ceridust? 9615 A. The micronized polyethylene or polythethylene-containing wax is present in the liquid additive composition in an amount of 0.5 to 6 wt %, such as 1 to 5 wt %, such as 1 to 4 wt %, such as 2 to 4 wt %.

[0091] Films

[0092] The liquid additive composition of the invention unexpectedly improves both the clarity of a film (such as a cast or blown film) and the film's surface appearance (such as reducing or eliminating sharkskin defects). In addition, during the preparation of a film, the presence of the liquid additive composition provides multiple advantages, such as reducing die head build-up due to the affinity of the composition to metal, increasing throughput by creating a low surface energy coating inside the processing equipment, shortening color change transitions, reducing degradation of the product; improving batch easy flow and lowering equipment torque and pressure (psi).

[0093] Letdown ratio (LDR) provides a means of identifying the concentration usage rate of the liquid additive composition of the invention. For example, use of 1 gram of the liquid additive composition for every 99 grams of the polymer/resin to be processed (100:1) results in a 1% LDR. Use of 2 grams of the liquid additive composition for every 98 grams of the polymer/resin to be processed (50:1) results in a 2% LDR and so forth. It was observed that for films, desirable results were achieved with a LDR in a range from 0.005% to 5%, such as 0.005% to 3%, such as 0.01% to 3%, such as 0.01% to 2%, such as 0.01% to 1%.

[0094] It was also unexpectedly observed that an embodiment of the liquid additive composition containing Kynar-Flex? 5301 as the polyvinylidene fluoride component was preferred for use at processing temperatures up to 500? F. (i.e., a low temperature additive composition) while in an embodiment of the liquid additive composition containing Kynar-Flex? 3121 as the polyvinylidene fluoride component was preferred for use at processing temperatures greater than 500? F., such as up to 2000? F. (i.e., a high temperature additive composition). Typically, the low temperature additive composition was observed to visually provide a moderate clarifying effect, improve transmittance with increasing letdown ratios (LDR) and requires third-party pulverizing. In contrast, in an exemplary embodiment, the high temperature additive composition was typically observed to visually provide a significant clarifying effect, exhibit optimal transmittance at lower letdown ratios (LDR) and did not require pulverizing.

[0095] Masterbatches

[0096] Masterbatches consist of a polymer matrix (i.e., a carrier) and high loadings of pigments and/or other additives, where the polymer matrix is either the same as or compatible with the polymer to which the masterbatch will be added. The liquid additive compositions of the invention are suitable for enhancing the performance of a masterbatch by facilitating the passage of masterbatch material through processing equipment in which plastics are prepared. The resulting plastics typically exhibit superior properties. In an exemplary embodiment, the liquid additive composition is present in a masterbatch is in a range of 0.05 to 90% by weight, such as 1 to 80% by weight, such as 5 to 80% by weight such as 10 to 70% by weight, such as 15 to 70% by weight, such as 20 to 60% by weight, such as 25 to 55% by weight, where the % by weight is based on the total weight of the masterbatch.

[0097] Extrusion Blow Molding

[0098] The benefits achieved using the liquid additive composition of the invention during extrusion blow molding is substantially similar to the benefits achieved when using the liquid additive composition in the preparation of cast or blown films as described herein.

EXAMPLES

[0099] The liquid additive compositions were prepared with the objective of achieving homogenous rheology, suitable flow and maximum loading of ingredients. A secondary objective was to develop liquid additive compositions as liquid masterbatches that exhibit minimal or insignificant settling upon storage.

Example 1. Preparation of a Low Temperature Liquid Additive Composition

[0100] Indopol? H-25 Indopol? L-14 and a 1:1 mixture of Solplus? K240 and Indopol? L-14 were mixed together to a temperature of 110? F. in a mixing container followed by the addition of Irgafos? 168, Rianox 1076, Ceridust? 3620 and pulverized Kynar-Flex? 5301. After mixing, the temperature was allowed to cool. When the temperature was below 80? F., HDK? N20 silica was added until it was evenly dispersed, with no clumps visible.

Example 2. Preparation of a High Temperature Liquid Additive Composition

[0101] Indopol? H-25, Indopol? L-14 and a 1:1 mixture of Solplus? K240 and Indopol? L-14 were mixed together to a temperature of 110? F. in a mixing container followed by the addition of Irgafos? 168, Rianox 1076, Ceridust? 3620 and non-pulverized Kynar-Flex? 3121. After mixing, the temperature was allowed to cool. When the temperature was below 80? F., HDK? N20 silica was added until it was evenly dispersed, with no clumps visible.

[0102] Results and Discussion

[0103] FIG. 1 shows that all of the tested additive compositions of the present invention exhibited an improved clarifying effect in LLDPE when compared to virgin LLDPE. The most significant clarifying result overall was achieved with Kynar Flex? 3121 at 0.015% LDR. The most significant clarifying result with the lowest LDR was achieved with Kynar Flex? 3121. The clarifying result achieved with Kynar Flex? 5301 was improved proportional to the LDR. FIGS. 2 and 3 show the difference in improvement in clarity in a LLDPE resin containing different amounts of an exemplary additive composition of LLDPE the present invention.

[0104] All patents/publications cited herein are incorporated by reference in their entireties.