Reinforced polyester structural components

Abstract

An article of manufacture comprising a polyester composition, the article comprising, as measured by differential scanning calorimetry with a heating rate of 20 C per minute on first heating according to ASTM D3418, at least two different crystalline melting temperatures, wherein a first crystalline melting temperature and a second crystalline melting temperature are each independently 200-290 C; and a first heat of fusion and a second heat of fusion that are each independently at least 3 J/g, preferably wherein a ratio of the first heat of fusion to the second heat of fusion is 1:5-5:1, wherein the polyester composition comprises a first polyester having a phosphorous content of greater than or equal to 20 ppm, a second polyester, and 5-50 weight percent of a plurality of fibers, based on the total weight of the polyester composition, wherein the plurality of fibers have a diameter of 5-25 micrometers.

1 . An article of manufacture comprising a polyester composition, the article comprising, as measured by differential scanning calorimetry with a heating rate of 20° C. per minute on first heating according to ASTM D3418,
 at least two different crystalline melting temperatures, wherein a first crystalline melting temperature and a second crystalline melting temperature are each independently 200-290° C.; and 
 a first heat of fusion and a second heat of fusion that are each independently at least 3 J/g, 
 wherein the polyester composition comprises
 a first polyester having a phosphorous content of greater than or equal to 20 ppm by weight, based on the total weight of the polyester composition, 
 a second polyester, and 
 5 to 50 weight percent of a plurality of fibers, based on the total weight of the polyester composition, wherein the plurality of fibers have a diameter of 5 of 25 micrometers. 
 
 
     
     
         2 . The article of  claim 1 , further comprising, as measured by differential scanning calorimetry with a cooling rate of 20° C. per minute on first cooling according to ASTM D3418,
 at least two different crystallization temperatures, wherein a first crystallization temperature and a second crystallization temperature are each independently 180 to 290° C.; and 
 a first heat of crystallization and a second heat of crystallization that are each independently −3 J/g or less. 
 
     
     
         3 . The article of  claim 1 , wherein the article has one or more of
 a tensile modulus of at least 6,000 MPa, as measured at 23° C. with a crosshead speed of 50 mm per minute according to ASTM D638;   a tensile strength at yield of at least 70 MPa, as measured at 23° C. with a crosshead speed of 50 mm per minute according to ASTM D638;   a heat deflection temperature of at least 180° C., as measured at 0.45 MPa according to ASTM D648; and   a melt volume flow rate of 10 to 80 cm 3 /10 minutes, as measured at 265° C. with a 2.16 kg loading for 6 minutes according to ASTM D1238.   
     
     
         4 . The article of  claim 1 , wherein the first polyester has
 a weight-average molecular weight of 15,000-80,000 grams per mole, as measured by gel permeation chromatography using polystyrene standards;   a carboxylic COOH end group content of greater than 20 millimole equivalents per kilogram;   a hydroxy OH end group content of greater than 20 millimole equivalents per kilogram;   a ratio of hydroxy end groups to carboxylic end groups of at least 1.3:1; and   a metal content of greater than 10 ppm by weight but less than 200 ppm by weight, wherein the metal is titanium, zirconium, zinc, antimony, germanium, cobalt, tin, or a combination thereof.   
     
     
         5 . The article of  claim 1 , wherein the polyester composition comprises
 10 to 60 weight percent of the first polyester, based on the total weight of the polyester composition, wherein the first polyester comprises a poly(ethylene terephthalate); and   10 to 85 weight percent of the second polyester, based on the total weight of the polyester composition, wherein the second polyester comprises a poly(butylene terephthalate).   
     
     
         6 . The article of  claim 1 , wherein the plurality of fibers comprises a plurality of chopped glass fiber, long glass fiber, glass filament, woven glass fiber, carbon fiber, woven carbon fiber, ceramic fiber, or a combination thereof. 
     
     
         7 . The article of  claim 1 , wherein the polyester composition further comprises
 0.01 to 0.5 weight percent of a stabilizer, based on the total weight of the polyester composition;   0.01 to 8 weight percent of a nucleant, based on the total weight of the polyester composition;   0.01 to 2 weight percent of a mold release agent, based on the total weight of the polyester composition; and   0 to 5 weight percent of a colorant, based on the total weight of the polyester composition.   
     
     
         8 . The article of  claim 1 , wherein the polyester composition further comprises 1 to 30 weight percent of an impact modifier, based on the total weight of the polyester composition. 
     
     
         9 . A polyester prepreg comprising the article of  claim 1 . 
     
     
         10 . A polyester composite produced by consolidating the polyester prepreg of  claim 9 . 
     
     
         11 . The polyester composite of  claim 10 , wherein the prepreg layers are in the form of continuous unidirectional fiber-reinforced polyester tapes. 
     
     
         12 . The polyester composite of  claim 11 , wherein the continuous unidirectional fiber-reinforced polyester tapes are oriented in the same direction and the composite has one or more of
 flexural strength in the machine direction and transverse direction, independently, of greater than 20 MPa, wherein the ratio of the flexural strength in the machine direction to the flexural strength in the transverse direction is less than 2:1, as measured according to ASTM D7264;   flexural modulus in the machine direction and transverse direction, independently, of greater than 200 GPa, wherein the ratio of the flexural modulus in the machine direction to the flexural modulus in the transverse direction is less than 2:1, as measured according to ASTM D7264;   a fiber volume fraction of 15 to 80%; and   an average density of 1.3 to 2.4 g/cm 3 , as measured according to ASTM D792.   
     
     
         13 . A polymer reinforcement comprising the article of  claim 1 , wherein the polymer reinforcement has a hollow multi-chambered structure having a hexagonal geometry. 
     
     
         14 . A structural body comprising
 a hollow component comprising walls that define a channel having a major axis; and   the polymer reinforcement of  claim 13 ,   wherein the polymer reinforcement is located in the channel, and   wherein the hollow multi-chambered structure comprises secondary channels that are oriented perpendicular or parallel to the major axis.   
     
     
         15 . A method of manufacturing the polyester composite of  claim 10 , the method comprising
 coating a substrate with a blend comprising the first polyester and the second polyester to form a coated substrate, wherein the substrate comprises the plurality of fibers;   heating the coated substrate at a first temperature to form a polyester prepreg;   layering a plurality of polyester prepregs; and   heating the plurality of polyester prepregs at a second temperature under pressure to form the polyester composite.   
     
     
         16 . The article of  claim 5 , wherein the polyester composition comprises
 20 to 50 weight percent of the first polyester, based on the total weight of the polyester composition, wherein the first polyester comprises a poly(ethylene terephthalate); and   20 to 60 weight percent of the second polyester, based on the total weight of the polyester composition, wherein the second polyester comprises a poly(butylene terephthalate).   
     
     
         17 . The article of  claim 16 , wherein the second polyester comprises a first poly(butylene terephthalate) and a second poly(butylene terephthalate), and wherein
 an intrinsic viscosity of the first poly(butylene terephthalate) is different than an intrinsic viscosity of the second poly(butylene terephthalate); or   a weight average molecular weight of the first poly(butylene terephthalate) is different than a weight average molecular weight of the second poly(butylene terephthalate); or   both the intrinsic viscosity and the weight average molecular weight are different.   
     
     
         18 . The article of  claim 7 , wherein the polyester composition further comprises, based on the total weight of the composition:
 0.01 to 0.3 weight percent of the stabilizer, the stabilizer comprising a hindered phenol, phosphite, phosphonite, thioester, or a combination thereof;   0.05 to 5 weight percent of the nucleant, the nucleant comprising talc, silica, siloxane, clay, alkaline carboxylate salt, or a combination thereof;   0.1 to 0.8 weight percent of the mold release agent, the mold release agent comprising a fatty acid ester, a wax, a polyolefin, or a combination thereof; and   0.1 to 5 weight percent of the colorant, the colorant comprising carbon black, a dye, a pigment, or a combination thereof.   
     
     
         19 . The article of  claim 8 , wherein the polyester composition further comprises 1 to 15 weight percent of the impact modifier, based on the total weight of the polyester composition, the impact modifier comprising an alkyl (meth)acrylate copolymer, (meth)acrylic ester-butadiene-styrene, acrylonitrile-butadiene-styrene, styrene-butadiene, styrene-ethylene-butylene-styrene, a poly(ether ester) block copolymer, a polyethylene-α olefin copolymer, styrene-isoprene-styrene triblock copolymer, or a combination thereof.