Polyamide-polyester block copolymers

Block copolymers consisting of polyamide and polyester blocks can form through melt 

Block polyester-polyamides also form through initiation of ring-opening polymerizations of 

If the polyamide has terminal amine groups at both ends, then triblock copolymers form. 

These materials were reviewed as a special class of block copolymersThey are linear polyaddition products of diisocyanates containing nonrandom distributions of ionic centers. The preparations are similar to those of polyurethane elastomers that are described in Chapter 6. One example is a material prepared from a high molecular weight polyester that is free from ionic centers and that is terminated by isocyanate groups at each end. The prepolymer is coupled with AT-methyl-amino-2,2 -diethanol to form a segmented polymer  

Similar products form from isocyanate-terminated polyethers. These materials can be crosslinked with difunctional quatemizing agents, such as l,4-bis(chloromethyl)benzene  

Block copolymers consisting of polyamide and polyester blocks can form through melt blending [426]. The reactions probably involve aminolyses of the terminal ester groups of the polyesters by the terminal amine groups of the polyamides. Ester interchange catalysts accelerate the reaction [427]. 

Block polyester-polyamides also form through initiation of ring opening polymerizations of lactones by the terminal amine groups of the polyamides [428]  

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PA/PET blends polyamide-polyester block copolymer Maresca Shafer, 1988... 

How can polyurethane-polyamide and polyamide-polyester block copolymers be formed Explain and show chemical reactions. 

PA/PET blends Polyamide-polyester block copolymer Maresca and Shafer 1988... 

Amorphous PA or PARA, with either PEST, PC, PEC, or PAr A polyamide-polyester block copolymer, PA-b-PEST Maresca and Shafer 1988... 

Polyamide-polyester block copolymers CORI Good control of the reaction via successive feeding strategies Kim and White 2005... 

It has also been found relatively easy to polymerize new block copolymers of interest, which can serve for instance as compatibilizing agents. This has been notably the case with polyamide-polyester block copolymers [239,240]. These were effective compatibiUzers with polyvinyl chloride-polyamide 12, polyvinyl chloride-ethylene propylene rubber, and polyvinyl chloride polypropylene [240]. 

Multiblock Copolymers. Replacement of conventional vulcanized mbber is the main appHcation for the polar polyurethane, polyester, and polyamide block copolymers. Like styrenic block copolymers, they can be molded or extmded using equipment designed for processing thermoplastics. Melt temperatures during processing are between 175 and 225°C, and predrying is requited scrap is reusable. They are mostiy used as essentially pure materials, although some work on blends with various thermoplastics such as plasticized and unplasticized PVC and also ABS and polycarbonate (14,18,67—69) has been reported. Plasticizers intended for use with PVC have also been blended with polyester block copolymers (67). 

S—EB—S (compounds) polyurethane/elastomer block copolymers polyester/elastomer block copolymers polyamide/elastomer block copolymers polyetherimide/polysiloxane block copolymers polypropylene/EPDM or EPR blends polypropylene/EPDM dynamic vulcanizates polypropylene/butyl rubber dynamic vulcanizates polypropylene/natural rubber dynamic vulcanizates polypropylene/nitrile rubber dynamic vulcanizates PVC/ nitrile rubber blends... 

Polycarbonate has been blended with commercial polyamides (PA-66 and PA-6), in order to improve its poor solvent resistance while maintaining a reasonable level of heat resistance and toughness. However, simple blends of polycarbonate and polyamides were highly incompatible and hence not useful. Several different additives such as phenoxy resins, polyester amide elastomers in combination with maleated polyolefins, polyetheramide block copolymers, and polyamide-polyacrylate block copolymers have been used as potential compatibilizers and impact modifiers. 

Besides the thermoplastic elastomers based on poly(styrene-6-elastomer- -styrene) block copolymers, five others are of commercial importance polyurethane/elastomer block copolymers, polyester/elastomer block copolymers, polyamide/elastomer block copolymers, polyolefin block copolymers, and polyetherimide/polysiloxane block copolymers. All five have the multiblock A-B-A-B. structure. The morphology of the polyurethane, polyester,... 

Multiblock Copolymers Polyurethane/elastomer block copolymers Polyester/elastomer block copolymers Polyamide/elastomer block copolymers Polyethylene/poly(a-olefin) block copolymers... 

Other Uses. Large quantities of hydrocarbon resins are used in mastics, caulks, and sealants (qv). Polymers for these adhesive products include neoprene, butyl mbber, polyisoprene, NR, SBR, polyisobutylene, acryHcs, polyesters, polyamides, amorphous polypropylene, and block copolymers. These adhesives may be solvent or water-borne and usually contain inorganic fillers. 

Thermoplastic polyester rubbers are also block copolymers of polyethers and polyesters. The polyester groups are capable of crystallisation and the crystal structures act like cross-links. These materials have good hydrocarbon resistance. Similar thermoplastic polyamide rubbers are also now available. 

Polyamide block copolymer with polyether/polyester PVC... 

HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HNS NTO NTO/HMX NTO/HMX NTO/HMX PETN PETN PETN PETN PETN PETN PETN PETN PETN PETN RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX TATB/HMX Cariflex (thermoplastic elastomer) Hydroxy-terminated polybutadiene (polyurethane) Hydroxy-terminated polyester Kraton (block copolymer of styrene and ethylene-butylene) Nylon (polyamide) Polyester resin-styrene Polyethylene Polyurethane Poly(vinyl) alcohol Poly(vinyl) butyral resin Teflon (polytetrafluoroethylene) Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Cariflex (block copolymer of butadiene-styrene) Cariflex (block copolymer of butadiene-styrene) Estane (polyester polyurethane copolymer) Hytemp (thermoplastic elastomer) Butyl rubber with acetyl tributylcitrate Epoxy resin-diethylenetriamine Kraton (block copolymer of styrene and ethylene-butylene) Latex with bis-(2-ethylhexyl adipate) Nylon (polyamide) Polyester and styrene copolymer Poly(ethyl acrylate) with dibutyl phthalate Silicone rubber Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Epoxy ether Exon (polychlorotrifluoroethylene/vinylidine chloride) Hydroxy-terminated polybutadiene (polyurethane) Kel-F (polychlorotrifluoroethylene) Nylon (polyamide) Nylon and aluminium Nitro-fluoroalkyl epoxides Polyacrylate and paraffin Polyamide resin Polyisobutylene/Teflon (polytetrafluoroethylene) Polyester Polystyrene Teflon (polytetrafluoroethylene) Kraton (block copolymer of styrene and ethylene-butylene)... 

Besides the use of micromolecular multiinitiators, block copolymers can be obtained from macromolecular initiators. In a first step, a polymeric initiator is generally synthesized by reacting a mono- or difunctional polymer with a functional initiator. Various macromolecular initiators were prepared in this way including quite different sequences polystyrene [13, 18, 19, 25, 26], poly(dimethylsiloxane) [27], polymethylmethacrylate) [13,15,28], polyvinylacetate [28], polyvinylchloride [29, 30], polyesters [30], polycarbonate [31,32], polybutadiene [13, 25, 33], polyamide [34], polyethylene glycol) [35] or polyaromatic [36], An excellent review of the synthesis and uses of such macroinitiators was written by Nuyken and Voit [37]. Thus, only few typical examples are going to be mentioned below. 

This characteristic feature of cationic polymerization of THF allows the important synthetic application of this process for preparation of oli-godiols used in polyurethane technology and in manufacturing of block copolymers with polyesters and polyamides (cf., Section IV.A). On the other hand, the cationic polymerization of THF not affected by contribution of chain transfer to polymer is a suitable model system for studying the mechanism and kinetics of cationic ring-opening polymerization. 

One simple idea is that styrenic block copolymers are almost never used as a stand-alone 100% neat polymer for any application or use. We tend to think about polymers in terms of this plastic soda bottle is polyester, or this carpet fiber is polyamide, or this house siding is PVC, or this garbage bag film is polyethylene , fully understanding and meaning that virtually 100% of the named object is that polymer. Our brains usefully process the named polymer properties set (as neat polymer) into the desired and required property set for its application. Life is simple in the 100% world. It is intuitive, and what we seem to know makes sense, looking either way properties wise, to why this polymer is used for this application. 

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