Method to establish viscosity as a function of shear rate for in-situ polymerized nanonylon via chain extension
View Patent ↗Chain-extended nanonylon is made from the reaction of in-situ polymerized nanonylon and chain-extending agents. Knowing the viscosity/shear rate curve for a thermoplastic polymer to be replaced, such as nylon, the method of the present invention allows via adjustment of organoclay concentration and chain extension of the nylon polymer and other reaction factors to achieve a chain-extended, in-situ polymerized nanonylon to have a viscosity/shear rate curve that essentially matches the viscosity/shear rate curve for that neat nylon within a commercially operable shear rate.
1. A method of making a chain extended in-situ polymerized nanonylon, suitable for extruding or molding without extensive processing alterations from processing conditions employed for a polymer targeted for replacement, comprising the steps of:
(a) establishing via experimentation a viscosity/shear rate curve for the polymer targeted for replacement;
(b) selecting an in-situ polymerized nanonylon having a given concentration of organoclay desired for improvement of performance properties;
(c) selecting a chain extending agent for the nanonylon;
(d) establishing reaction factors of the chain extending agent for the nanonylon;
(e) using the reaction factors, reacting the in-situ polymerized nanonylon with the chain extending agent present at a given concentration sufficient to produce a chain-extended, in-situ polymerized nanonylon that has a viscosity/shear rate curve that essentially matches the viscosity/shear rate curve for the polymer targeted for replacement.
2. The process of claim 1 , wherein the chain extending agent is selected from the group consisting of carbodiimides, carbodiimide hydrochlorides, multi-functional epoxies, carbonylbiscaprolactames, multi-functional acrylic oligomers, and combinations thereof, to form the chain-extended nanonylon.
3. The process of claim 1 , wherein the concentration of organoclay ranges from about a minimally perceptible amount to about 8 percent by weight, and wherein the polymerized nanonylon provides performance properties by the introduction of the organoclay to the nylon, which neat nylon, or other polymer, targeted to be replaced does not possess.
4. The process of claim 1 , wherein the weight average molecular weight of the in-situ polymerized nanonylon ranges from about 50,000 to about 85,000.
5. The process of claim 1 , wherein the weight average molecular weight of the in-situ polymerized nanonylon is about 75,000.
6. The process of claim 1 , wherein the in-situ polymerized nanonylon comprises one or a number of polyamides prepared from one or more epsilon lactams.
7. The process of claim 1 , wherein the in-situ polymerized nanonylon comprises polycaprolactam (nylon 6), poly(hexamethylene adipamide) (nylon 6,6), poly(hexamethylene sebacamide) (nylon 6, 10), poly(11-aminondecanoic acid) (nylon 11), poly(12-aminododecanoic acid) (nylon 12) and combinations thereof.
8. The process of claim 1 , wherein the reaction of the in-situ polymerized nanonylon in step (f) occurs in the presence of an optional additive selected from the group consisting of optional additives include adhesion promoters; biocides (antibacterials, fungicides, and mildewcides), anti-fogging agents; anti-static agents; bonding, blowing and foaming agents; dispersants; fillers and extenders; fire and flame retardants and smoke suppresants; impact modifiers; initiators; lubricants; micas; pigments, colorants and dyes; plasticizers; processing aids; release agents; silanes, titanates and zirconates; slip and anti-blocking agents; stabilizers; stearates; ultraviolet light absorbers; viscosity regulators; waxes; and combinations of them.
9. The process of claim 1 , wherein the reaction of in-situ polymerized nanonylon in step (f) occurs in the presence of another resin selected from the group consisting of polyolefins, polyamides, polyimides, polycarbonates, polyesters, polysulfones, polylactones, polyacetals, acrylonitrile-butadiene-styrene resins (ABS), polyphenyleneoxide (PPO), polyphenylene sulfide (PPS), polystyrene, styrene-acrylonitrile resins (SAN), styrene maleic anhydride resins (SMA), aromatic polyketones (PEEK, PED, and PEKK) and mixtures thereof.
10. The process of claim 1 , wherein after the reacting step, further comprising the step (g) of reacting an endcapping agent with the chain-extended nanonylon, wherein the endcapping agent is selected from the group consisting of acetic anhydride, phthalic anhydride, hexamethyl disilazane, acetic acid, and cyclohexylamine.
11. The process of claim 1 , wherein the in-situ polymerized nanonylon is present in an amount ranging from about 10 to about 99.5 weight percent and the chain extending agent is present in an amount ranging from about 0.5 to about 20 weight percent.