Polyphthalamide

Last updated
Repeating unit of polyphthalamide Polyphthalamid.svg
Repeating unit of polyphthalamide

Polyphthalamide (aka. PPA, [1] High Performance Polyamide) is a subset of thermoplastic synthetic resins in the polyamide (nylon) family defined as when 55% or more moles of the carboxylic acid portion of the repeating unit in the polymer chain is composed of a combination of terephthalic (TPA) and isophthalic (IPA) acids. [2] The substitution of aliphatic diacids by aromatic diacids in the polymer backbone increases the melting point, glass transition temperature, chemical resistance and stiffness. [3] [4]

Contents

PPA based resins are molded into parts to replace metals in applications requiring high temperature resistance such as automotive powertrain components, the housing for high temperature electrical connectors and many other uses.

Formulated PPA granules ready for molding PPA-Polyphthalamide.png
Formulated PPA granules ready for molding

Structure

The diamines in PPAs are aliphatic. PA6T homopolymer melts at 371 °C, [5] which renders it intractable. To make usable polymers, it is necessary to lower the melting point, which can be achieved practically using either a longer diamine (with 9-12 carbon atoms) or by copolymerizing 6I.

Three copolymers have found commercial success: PA 6T/66, PA 6T/"DT" and PA6T/6I (with Isophthalic acid). [6] [7]

Polyphthalamid 6T.svg Polyphthalamide TPA/hexamethylenediamine (6T) repeat unit

Polyphthalamid DT.svg Polyphthalamide TPA/methylpentanediamine (DT) repeat unit

If more than 55% of the acid part of a PPA is made out of IPA, then the copolymer is amorphous. [3] Molar masses for PPAs made with direct polycondensation techniques range between 12,000 and 16,000 g/mol.

Properties

Compared to aliphatic polyamides, PPAs offer improved [8] [9] [10] [11]

The glass transition temperature of PPA increases as the amount of TPA increases. [3] If more than 55% of the acid part of a PPA is made out of IPA, then the copolymer is amorphous. [3] The properties of semicrystalline polymers v amorphous polymers are described elsewhere in detail. Briefly, crystallinity helps with chemical resistance and mechanical properties above the glass transition temperature (but below the melting point). Amorphous polymers are good in warpage and transparency.

Like aliphatic nylons, PPAs can be (in fact are almost invariably) modified with reinforcing agents such as glass fibers, tougheners and/or stabilizers.

Formulations with specific properties have been developed. For example, resins with ability to bond directly to elastomers to give plastic-rubber composites, and with approval for direct contact with drinking water and food. [12]

Polyphthalamide blends

The addition of aliphatic polyamides to PPAs (PPA/PA blend) lowers the melting point and glass transition temperature, which potentially makes these polyphthalamide blends easier to process when compared to higher melting/softening PPAs.

While there have been large investigations into PA/polyolefin blends, little has been published about the properties of PPA/ polyolefin blends. This may be due to the relatively high processing temperatures needed for PPA based resins compared to the temperature stability of polyolefins. PPA/PA/polyolefin blends exhibit a good balance of ductility, strength, stiffness, impact, and thermal performance, indicating that these types of materials should have commercial utility. [13]

Applications

Polyphthalamide based resins are injection moulded into parts that are used in a wide variety of applications. Automotive uses include fuel and coolant lines, pump wear rings, motor bobbin parts, fuel line connectors, water heater manifolds fuel modules, fuel cut-off valves, thermostat housing, air coolers, coolant pumps, and LED headlights. In electronics, the high melting point of PPA allows surface mount devices parts molded from PPA to be assembled using a lead-free soldering process. [12] PPAs are also used for USB-C connectors, [14] LED mounts and cable/wire protection. [10] Other applications for PPA based resins include gas pipes and supply lines for the oil industry (due to their ability to withstand high pressures), Medical applications such as tubing for catheters, in personal care, for toothbrush bristles as well as hairbrushes. PPAs are also used in sports equipment, valve bodies for showers, bushings and bearing pads in aircraft engines

Lifecycle impact

PPAs, as any thermoplastic, are theoretically fully recyclable by remelting, and as a condensation polymer by depolymerization. Commercial recycling requires the cost of logistics and cleaning and processing to be lower than the cost of virgin polymer, which is not always the case. The PPA waste that produces energy can be recovered at incineration plants. The best recovery options depend on many conditions such as local legislation, plastic part design, access to sorting facilities, and recycling costs.

Commercial suppliers

Related Research Articles

<span class="mw-page-title-main">Nylon</span> Family of synthetic polymers originally developed as textile fibers

Nylon is a generic designation for a family of synthetic polymers composed of polyamides. Nylon is a silk-like thermoplastic, generally made from petroleum, that can be melt-processed into fibers, films, or shapes. Nylon polymers can be mixed with a wide variety of additives to achieve many property variations. Nylon polymers have found significant commercial applications in fabric and fibers, in shapes, and in films.

<span class="mw-page-title-main">Petrochemical</span> Chemical product derived from petroleum

Petrochemicals are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable sources such as maize, palm fruit or sugar cane.

<span class="mw-page-title-main">Thermoplastic</span> Plastic that softens with heat and hardens on cooling

A thermoplastic, or thermosoft plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling.

A polyamide is a polymer with repeating units linked by amide bonds.

Polyamide-imides are either thermosetting or thermoplastic, amorphous polymers that have exceptional mechanical, thermal and chemical resistant properties. Polyamide-imides are used extensively as wire coatings in making magnet wire. They are prepared from isocyanates and TMA in N-methyl-2-pyrrolidone (NMP). A prominent distributor of polyamide-imides is Solvay Specialty Polymers, which uses the trademark Torlon.

A polyolefin is a type of polymer with the general formula (CH2CHR)n where R is an alkyl group. They are usually derived from a small set of simple olefins (alkenes). Dominant in a commercial sense are polyethylene and polypropylene. More specialized polyolefins include polyisobutylene and polymethylpentene. They are all colorless or white oils or solids. Many copolymers are known, such as polybutene, which derives from a mixture of different butene isomers. The name of each polyolefin indicates the olefin from which it is prepared; for example, polyethylene is derived from ethylene, and polymethylpentene is derived from 4-methyl-1-pentene. Polyolefins are not olefins themselves because the double bond of each olefin monomer is opened in order to form the polymer. Monomers having more than one double bond such as butadiene and isoprene yield polymers that contain double bonds (polybutadiene and polyisoprene) and are usually not considered polyolefins. Polyolefins are the foundations of many chemical industries.

Zytel is a trademark owned by Celanese and used for a number of different high strength, abrasion and impact resistant thermoplastic polyamide formulations of the family more commonly known as nylon. The Zytel product line is based mostly on nylon 66, but also includes grades based on nylon 6 as a matrix, long chain nylons such as nylon 610, and copolymers including a transparent resin called Zytel 330. Resins based on polyphthalamides are branded 'Zytel HTN'. The Zytel product range takes advantage of the fact that nylons are one of the most compatible polymers with modifiers and so offers grades with varying degrees of fiberglass, from 13% to 60%,, rubber toughened resins, flame retarded grades. Nylon resins with mineral reinforcement are branded 'Minlon'.

<span class="mw-page-title-main">Hot-melt adhesive</span> Glue applied by heating

Hot-melt adhesive (HMA), also known as hot glue, is a form of thermoplastic adhesive that is commonly sold as solid cylindrical sticks of various diameters designed to be applied using a hot glue gun. The gun uses a continuous-duty heating element to melt the plastic glue, which the user pushes through the gun either with a mechanical trigger mechanism on the gun, or with direct finger pressure. The glue squeezed out of the heated nozzle is initially hot enough to burn and even blister skin. The glue is sticky when hot, and solidifies in a few seconds to one minute. Hot-melt adhesives can also be applied by dipping or spraying, and are popular with hobbyists and crafters both for affixing and as an inexpensive alternative to resin casting.

<span class="mw-page-title-main">Polyester</span> Category of polymers, in which the monomers are joined together by ester links

Polyester is a category of polymers that contain the ester functional group in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include naturally occurring chemicals, such as in plants and insects, as well as synthetics such as polybutyrate. Natural polyesters and a few synthetic ones are biodegradable, but most synthetic polyesters are not. Synthetic polyesters are used extensively in clothing.

Thermoplastic elastomers (TPE), sometimes referred to as thermoplastic rubbers, are a class of copolymers or a physical mix of polymers that consist of materials with both thermoplastic and elastomeric properties. While most elastomers are thermosets, thermoplastics are in contrast relatively easy to use in manufacturing, for example, by injection moulding. Thermoplastic elastomers show advantages typical of both rubbery materials and plastic materials. The benefit of using thermoplastic elastomers is the ability to stretch to moderate elongations and return to its near original shape creating a longer life and better physical range than other materials. The principal difference between thermoset elastomers and thermoplastic elastomers is the type of cross-linking bond in their structures. In fact, crosslinking is a critical structural factor which imparts high elastic properties.

FKM is a family of fluorocarbon-based fluoroelastomer materials defined by ASTM International standard D1418, and ISO standard 1629. It is commonly called fluorine rubber or fluoro-rubber. FKM is an abbreviation of Fluorine Kautschuk Material. All FKMs contain vinylidene fluoride as a monomer. Originally developed by DuPont, FKMs are today also produced by many companies, including: Daikin (Dai-El), 3M (Dyneon), Solvay S.A. (Tecnoflon), HaloPolymer (Elaftor), Gujarat Fluorochemicals (Fluonox), and several Chinese manufacturers. Fluoroelastomers are more expensive than neoprene or nitrile rubber elastomers. They provide additional heat and chemical resistance. FKMs can be divided into different classes on the basis of either their chemical composition, their fluorine content, or their cross-linking mechanism.

Polybutylene (polybutene-1, poly(1-butene), PB-1) is a polyolefin or saturated polymer with the chemical formula (CH2CH(Et))n. Not be confused with polybutene, PB-1 is mainly used in piping.

Chain shuttling polymerization is a dual-catalyst method for producing block copolymers with alternating or variable tacticity. The desired effect of this method is to generate hybrid polymers that bear the properties of both polymer chains, such as a high melting point accompanied by high elasticity. It is a relatively new method, the first instance of its use being reported by Arriola et al. in May 2006.

<span class="mw-page-title-main">Zinc borate</span> Chemical compound

Zinc borate is an inorganic compound, a borate of zinc. It is a white crystalline or amorphous powder insoluble in water. Its toxicity is low. Its melting point is 980 °C.

Poly(<i>p</i>-phenylene oxide) Chemical compound

Poly(p-phenylene oxide) (PPO), poly(p-phenylene ether) (PPE), often referred to simply as polyphenylene oxide, is a high-temperature thermoplastic. It is rarely used in its pure form due to difficulties in processing. It is mainly used as blend with polystyrene, high impact styrene-butadiene copolymer or polyamide. PPO is a registered trademark of SABIC Innovative Plastics B.V. under which various polyphenylene ether resins are sold.

Novel polymeric alloy (NPA) is a polymeric alloy composed of polyolefin and thermoplastic engineering polymer with enhanced engineering properties. NPA was developed for use in geosynthetics. One of the first commercial NPA applications was in the manufacturer of polymeric strips used to form Neoloy® cellular confinement systems (geocells).

<span class="mw-page-title-main">Aluminium diethyl phosphinate</span> Chemical compound

Aluminium diethyl phosphinate is a chemical compound with formula Al(C
4
H
10
O
2
P
)3. It decomposes above 300 °C.

Nylon 12 is a nylon polymer with the formula [(CH2)11C(O)NH]n. It is made from ω-aminolauric acid or laurolactam monomers that each have 12 carbons, hence the name ‘Nylon 12’. It is one of several nylon polymers.

<span class="mw-page-title-main">Nylon 46</span> Chemical compound

Nylon 46 is a high heat resistant polyamide or nylon. DSM is the only commercial supplier of this resin, which markets under the trade name Stanyl. Nylon 46 is an aliphatic polyamide formed by the polycondensation of two monomers, one containing 4 carbon atoms, 1,4-diaminobutane (putrescine), and the other 6 carbon atoms, adipic acid, which give nylon 46 its name. It has a higher melting point than nylon 6 or nylon 66 and mainly used in applications which must withstand high temperatures.

<span class="mw-page-title-main">2-Methylpentamethylenediamine</span> Chemical compound

2-Methylpentamethylenediamine is an organic compound part of the amine family with the formula H2NCH2CH2CH2CH(CH3)CCH2NCH2. A colorless liquid, this diamine is obtained by the hydrogenation of 2-methylglutaronitrile.

References

  1. Care should be taken not to confuse this with 'PP&A', which stands for polyester, polyamide and acrylate polymers - all of which are used to make fibres. See doi : 10.1016/j.jhazmat.2019.02.067.
  2. ASTM standard D 5336 -15a
  3. 1 2 3 4 Cousin, Thibault; Galy, Jocelyne; Dupuy, Jérôme (2012). "Molecular modelling of polyphthalamides thermal properties: Comparison between modelling and experimental results". Polymer. 53 (15): 3203–10. doi:10.1016/j.polymer.2012.05.051.
  4. Harper, Charles A. (2002). Handbook of plastics, elastomers, and composites. McGraw-Hill. pp. 51–52. ISBN   978-0-07-138476-6.
  5. Kohan, Melvin I, ed. (1995). Nylon Plastics Handbook. Munich: Hanser. p. 71. ISBN   978-1-56990-189-2.
  6. Glass; Walter; Kozielski, Gary; Martens, Marv. "High Performance Polyamides Fulfill Demanding Requirements for Automotive Thermal Management Components" (PDF). DuPont. Retrieved 26 March 2016.
  7. 1 2 "Grivory HT". www.emsgrivory.com. EMS Chimie. Retrieved 25 May 2015.
  8. "Amodel PPA". Solvay. Retrieved 26 March 2016.
  9. "Grivory HT". EMS Grivory. Retrieved 26 March 2016.
  10. 1 2 3 "Zytel HTN". DuPont. Retrieved 26 March 2016.
  11. "Practical Guide to High Performance Engineering Plastics" (PDF). SmithersRapra. Retrieved 26 March 2016.
  12. 1 2 Evonik Industries, http://www.vestamid.com/product/vestamid/en/products-services/pages/default.aspx
  13. Desio, G.P. (1996). "Characterization and properties of polyphthalamide/polyamide blends and polyphthalamide/polyamide/polyolefin blends". J Vinyl Addit Technol. 2 (3): 229–234. doi:10.1002/vnl.10131.
  14. Zistler, Andrew (December 11, 2015). "DuPont's Zytel HTN selected for use in USB Type-C 3.1 connectors". connectortips.com. EE World. Retrieved 26 March 2016.
  15. "Introduction to Rilsan HT" (PDF). Arkema. Retrieved 26 March 2016.
  16. "PPAssion for perfection The Ultramid® Advanced portfolio: We provide the PPA you need..."
  17. 1 2 "HPPA Genestar PA9T - Auto applications" (PDF). Kuraray. Retrieved 26 March 2016.
  18. "Stanyl ForTii". DSM. Retrieved 26 March 2016.
  19. "Vestamid HT Plus" (PDF). Evonik. Retrieved 26 March 2016.
  20. Practical Guide to High Performance Engineering Plastics . SmithersRapra. 2011. p.  50. ISBN   9781847355775.
  21. "Amodel design guide" (PDF). Nevicolor. p. 13. Archived from the original (PDF) on 25 May 2015. Retrieved 24 Jan 2022.
  22. "Technical data sheet". IDES. Retrieved 25 May 2015.
  23. "Amodel A1133 datasheet". IDES. Retrieved 25 May 2015.