摘要:
Disclosed is a polyamide composition including at least one semi-aromatic copolyamide, said semi-aromatic copolyamide consisting essentially of about 25 to about 55 mole percent repeat units of the formula —C(O)(CH2)mC(O)NHCH2ArCH2NH— (I) and about 45 to about 75 mole percent repeat units of the formula —C(O)(CH2)mC(O)NH(CH2)nNH— (II) wherein m is 8, 10, and/or 12, n is 6, 10 and/or 12 and Ar is a meta-substituted benzene ring; and said polyamide has a melting point equal to or less than 225° C.; and 0.25 to 20 weight percent of one or more polyhydroxy polymer(s) having a number average molecular weight of at least 2000 and selected from the group consisting of ethylene/vinyl alcohol copolymer and poly(vinyl alcohol). Also disclosed are molded or extruded articles including the polyamide composition.
摘要:
Disclosed is a polyamide composition including at least one semi-aromatic copolyamide, said semi-aromatic copolyamide consisting essentially of about 25 to about 55 mole percent repeat units of the formula —C(O)(CH2)mC(O)NHCH2ArCH2NH— (I) and about 45 to about 75 mole percent repeat units of the formula —C(O)(CH2)mC(O)NH(CH2)nNH— (II) wherein m is 8, 10, and/or 12, n is 6, 10 and/or 12 and Ar is a meta-substituted benzene ring; and said polyamide has a melting point equal to or less than 225° C.; and 0.25 to 20 weight percent of one or more polyhydroxy polymer(s) having a number average molecular weight of at least 2000 and selected from the group consisting of ethylene/vinyl alcohol copolymer and poly(vinyl alcohol). Also disclosed are molded or extruded articles including the polyamide composition.
摘要:
Polyamides made from 1,6-hexanediamine, and the dicarboxylic acids 1,10-decandioic acid and/or 1,12-dodecanedioic acid, and terephthalic acid in specified proportions are particularly resistant to salt stressed (induced) corrosion cracking. This makes them particularly useful as vehicular parts which may be exposed to salts. Particularly when these polyamides contain tougheners and/or plasticizers they are especially useful for hoses and tubes.
摘要:
Disclosed is a polyamide composition including at least one semi-aromatic copolyamide, said semi-aromatic copolyamide consisting essentially of about 25 to about 55 mole percent repeat units of the formula —C(O)(CH2)mC(O)NHCH2ArCH2NH— (I) and about 45 to about 75 mole percent repeat units of the formula —C(O)(CH2)mC(O)NH(CH2)nNH— (II) wherein m is 8, 10, and/or 12, n is 6, 10 and/or 12 and Ar is a meta-substituted benzene ring; and said polyamide has a melting point equal to or less than 225° C.; and 0.1 to 15 weight percent of one or more polyhydric alcohols having more than two hydroxyl groups and having a number average molecular weight (Mn) of less than 2000. Also disclosed are molded or extruded articles including the polyamide composition.
摘要:
The present invention relates to the use of flexible hoses capable of handling high pressure fluids and providing a barrier against permeation loss in air conditioning and refrigeration systems. Such hoses are particularly suitable in air conditioning and refrigeration in which new, low global warming potential refrigerant alternatives are used.
摘要:
Multilayered polyamide composite articles comprising at least three layers that comprise aliphatic and semi-aromatic polyamides and that is better able to retain its mechanical properties at high temperatures and over long times are disclosed. Layers comprising aliphatic polyamides may optionally contain oxidation stabilizers. The articles may be in the form of tubes incorporated into a heat exchanger. Processes for their preparation are also provided.
摘要:
Polyamide compositions suitable for the inner layer of multi-layer tubular articles for circulating a heat transfer fluid composition within a refrigeration or air conditioning system are provided and including articles prepared from these compositions. Such compositions are particularly suitable in air conditioning and refrigeration applications and systems in which new, low global warming potential refrigerant alternatives are used.
摘要:
The present invention relates to the field of flexible hollow structure suitable to convey a refrigerant fluid and methods for their use. Disclosed hollow structures comprising a layer made of a resin composition comprising one or more semi-aromatic polyamides and one or more functionalized polyolefins show a balance of properties in terms of flexibility, permeation barrier against a refrigerant fluid and retention of properties upon heat and refrigerant fluid exposure.
摘要:
Disclosed is a multi-layer tube including: A) a first layer including a first layer composition including a1) about 25 to 100 weight percent of a semi-aromatic polyamide whose repeat units consist essentially of about 60 to about 85 molar percent of repeat units of the formula —C(O)(CH2)mC(O)NH(CH2)6NH— (I) wherein m is 8 and/or 10, and about 15 to about 40 molar percent of repeat units of the formula B) a second layer including a second layer composition including b1) 50 to 100 weight percent of poly(caprolactam); with the proviso that the first layer and second layer are in direct contact; and the weight percents are based upon the total weight of the first layer composition and the second layer composition, respectively.
摘要:
Disclosed is a melt-blended thermoplastic composition including: A) a polyamide composition including a) 55 to 90 weight percent semi-crystalline semi-aromatic copolyamide; wherein the semi-aromatic copolyamide has a DMA tan delta peak value of greater than or equal to 0.23; and heat of fusion of at least 20 J/g and b) 10 to 45 weight percent aliphatic homopolyamide; wherein the aliphatic homopolyamide has a DMA tan delta peak value of less than or equal to 0.21; and heat of fusion of at least 30 J/g; B) 0 to 45 weight percent polymeric toughener; C) 0 to 20 weight percent plasticizer; and D) 0 to 45 weight percent reinforcing agent; wherein said melt-blend composition has a glass transition and has a tan delta peak (E″/E′) value of 0.21 or lower at said glass transition. Further disclosed herein is a method for providing the melt-blended thermoplastic composition.