TH56909B - The process of making a container from a polyester polymer particle with a minimal intrinsic viscosity gradient. - Google Patents

Abstract

DC60 (16/05/48) Nowadays, a polymer particle with lt.V., surface and center, where lt.V. at the particle surface is Less than 0.25 dl / g, higher than lt.V. in the middle of the particle. Crystalline polyester particles are preferred to Prevents particles from sticking while drying, and where required is less than 10 ppm acetaldehyde. A polyester container, suitable preform or beverage bottle, is made by particle feeding. Crystalline polyester with at least 0.70 dl / g lt.V. to the extrusion area, melting the particles in the extrusion area to form a polyester polymer composition. That is molten, and formed into sheets or cast parts From the extruded molten polyester polymer, where at least part of the polyester particle has lt.V. on its surface, which is not deformed from lt. .V. In the middle of it is greater than 0.25 dl / g, and the particles are not polymerized in the hardened state. Such polyester compositions have lt.V. suitable for containers, Loss of lt.V. during melting process Less than the existing polyester. At present, it has been supplied with lt.V. polymer particles with lt.V., surface and center, where lt.V. at the surface of the particle is less than 0.25 dl / g. Than lt.V. in the middle of the particle. Crystalline polyester particles are preferred to Prevents particles from sticking while drying, and where required is less than 10 ppm acetaldehyde. A polyester container, suitable preform or beverage bottle, is made by particle feeding. Crystalline polyester with at least 0.70 dl / g lt.V. to the extrusion area, melting the particles in the extrusion area to form a polyester polymer composition. That is molten, and formed into sheets or cast parts From the extruded molten polyester polymer, where at least part of the polyester particle has lt.V. on its surface, which is not deformed from lt. .V. In the middle of it is greater than 0.25 dl / g, and the particles are not polymerized in the hardened state. Such polyester compositions have lt.V. suitable for containers, Loss of lt.V. during melting process Less than the existing polyester.

Claims (2)

Polyester polymer particles comprising a polyester polymer comprising: (a) a carboxylic acid component comprising at least 90 mol% of terephthalic acid residues, terephthalic acid derivatives, naphthalene-2,6-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid derivatives, or a mixture thereof, and (b) a hydroxyl component comprising at least 90 mol% of ethylene glycol residues, compared with 100 mol% of the carboxylic acid component residues and 100 mol% of the hydroxyl component residues in the polyester polyester, wherein the particles have a l t.V of at least 0.70 dL/g, and the l t.V at the particle surface is less than 0.25 dL/g more than l t.V at the particle center. 2. Particles of claim 1, wherein the particles have l t.V of at least 0.74 dL/g. 3. Particles of claim 2, wherein the particles have l t.V of at least 0.77 dL/g. 4. Particles of claim 2, wherein the l t.V at the particle surface is less than 0.20 dL/g more than l t.V at the particle center. 5. Particles of claim 1, wherein the l t.V at the particle surface is less than 0.15 dL/g more than l t.V at the particle center. 6. Particles of claim 1, wherein the particles have a degree of crystallinity of at least 25%. 7. Particles of claim 1, wherein the particles contain less than 10 ppm acetaldehyde. 8. Weight average polyester particles. At least 1.0 g per 100 particles, wherein each particle is a polyester particle of claim 1.9. The polyester particles of claim 1, wherein said polyester particles are impure polyester polymers. 1 0. The polyester particles of claim 1, wherein the polyester polymer has at least (a) a carboxylic acid component consisting of at least 92 mol% of terephthalic acid residues, or terephthalic acid derivatives, or a mixture thereof, and (b) a hydroxyl component consisting of at least 92 mol% of ethylene glycol residues, compared with 100 mol% of the polycarboxylic acid component residues and 100 mol% of the hydroxyl component residues in Polyester polymers.1 1. The particles of claim 1, wherein the l t.V. of the surface particles does not vary from the l t.V. of the particle at the center is greater than 0.10 dL/g.1 2. The particles of claim 11, wherein the l t.V. of the surface particles does not vary from the l t.V. of the particle at the center is greater than 0.20 dL/g.1 3. The particles of claim 11, wherein the polyester polymer has at least: (a) a carboxylic acid component consisting of at least 96 mol% of terephthalic acid residues, or terephthalic acid derivatives, or a mixture thereof, and (b) a hydroxyl component consisting of at least 96 mol% of ethylene glycol residues, with respect to 100 mol% of the carboxylic acid component residues and 100 mol% of the residue hydroxyl component in the polyester polymer.1 4. The particles of claim 13, wherein the particles have a degree of crystallinity of at least 25%.1 5. The particles of claim 1, comprising an aggregate of said particles having a volume of at least 1 m3.1 6. The particles of claim 15, wherein the average l t.V. difference between the l t.V. of the surface of the particles and the l t.V. of the center of the particles in the aggregate is not more than 0.20 dL/g.1 7. The particles of claim 16, wherein the average l t.V. difference is not more than 0.10 dL/g.1 8. The blow-molded container obtained from any one of the polyester polymer particles of claims 1-17.1 9. The beverage bottle obtained from the polyester particles. The polymer of claim 1.2. 0. Polyester particles having a degree of crystallinity of at least 25% and l t.V. of at least 0.70 dL/g, said particles having l t.V. at their surfaces and l t.V. at their centers, wherein l t.V. at the surface of the particles is less than 0.25 dL/g higher than l t.V. at the center of the particles. 2. 1. The particles of claim 20, wherein the polyester polymer has: (a) a carboxylic acid component comprising at least 90 mol% of terephthalic acid residues, or terephthalic acid derivatives, or a mixture thereof, and (b) a hydroxyl component comprising at least 90 mol% of ethylene glycol residues, compared with 100 mol% of the acid component residues. carboxylic and 100 mol % hydroxyl residues in the polyester polymer.2 2. Polyester particles of claim 21, wherein the degree of crystallinity is at least 35%, and the l t.V. of the particles is at least 0.74 dL/g.2 3. Polyester particles of claim 21, wherein the difference between the l t.V. of the particles at its surface and its center is 0.15 dL/g or less.2 4. Polyester particles of claim 23, wherein the difference is 0.05 dL/g or less.2 5. Blow-molded containers obtained from the polyester particles of claim 1 having a degree of crystallinity of at least 35%, and l t.V. of at least 0.77 dL/g, said blow-molded containers obtained without increasing the molecular weight of the pellets. By solid state polymerization.2 6. A process for making containers from polyester polymers, comprising feeding polyester particles having a degree of crystallinity of at least 15%, and an l t.V. of at least 0.70 dL/g, into an extrusion zone, melting the particles in the extrusion zone to form a molten polyester polymer composition, and forming sheets or molded parts from the extruded molten polyester polymer, wherein the polyester particles fed into the extrusion zone have a l t.V. at its surface less than 0.25 dL/g higher than the l t.V. at its center.2 7. The process of claim 26, wherein the l t.V. at the surface of the particles is less than 0.20 dL/g higher than the l t.V. at its center.2 8. The process of claim 27, wherein the difference between the l t.v. of the particles at its surface and its center is 0.10 dL/g or less. 2 9. The process of claim 28, wherein the difference is 0.05 dL/g or less. 3 0. The process of claim 26, wherein the molded part is a preform of a container. 3 1. The process of claim 30, comprising blow molding the preform into a beverage container. 3 2. The process of claim 31, wherein the container has a volume of 3 litres or less. 3 3. The process of claim 27, comprising drying the particles in the drying zone at a temperature of at least 140°C prior to melting the particles in the extrusion zone. 3 4. The process of claim 26, further comprising drying the particles prior to feeding the particles into the extrusion zone, wherein the particles are not polymerized in a solid state prior to drying.3 5. The process of claim 34, wherein the particles have an acetaldehyde level of 10 ppm or less prior to melting in the extrusion zone.3 6. The process of claim 26, wherein the polyester polymer particles comprise: (a) a carboxylic acid component comprising at least 90 mol % of terephthalic acid residues, or terephthalic acid derivatives, or a mixture thereof, and (b) a hydroxyl component comprising at least 90 mol % of ethylene glycol residues, with respect to 100 mol % of the carboxylic acid component residues and 100 mol % of the hydroxyl component residues in the polyester polymer, and at least 75% of the polyester polymer is the impure polymer.3 7. The process of claim 36, wherein the polyester polymer particles comprise: (a) a carboxylic acid component comprising at least 90 mol % of the carboxylic acid component residues, or a derivative thereof, or a mixture thereof, and (b) a hydroxyl component comprising at least 90 mol % of the ethylene glycol residues, with respect to 100 mol % of the carboxylic acid component residues and 100 mol % of the hydroxyl component residues in the polyester polymer, and at least 75% of the polyester polymer is the untainted polymer. consisting of at least 92 mol % of terephthalic acid residues, or terephthalic acid derivatives, or a mixture thereof, and (b) a hydroxyl component consisting of at least 92 mol % of ethylene glycol residues compared with 100 mol % of the carboxylic acid component residues and 100 mol % of the hydroxyl component residues in the polyester polymer.3 8. The process of claim 37, wherein the degree of crystallinity is at least 25%.3 9. The process of claim 26, wherein the degree of crystallinity is at least 35%.4 0. The process of claim 26, comprising an aggregate of said particles having a volume of at least 1 m3.4 1. The particles of claim 40, wherein the average l t.V. of the difference between the l t.V. of the surface of the particles and the l t.V. of the center of the particles in the aggregate is not more than 0.20 dL/m.4 2. The particles of claim 41, wherein the average l t.V. of the difference is not more than 0.10 dL/m.4 3. A blow molded container obtained from the particles. 26.4. 4. A preform obtained from the particles of claim 26.4. 5. Polyester particles having a particle weight of more than 1.0 g per 100 particles and less than 100 g per 100 particles, said particles, consisting of at least 75% unadulterated polyester polymer, comprising: (a) a carboxylic acid component comprising at least 90 mol% of terephthalic acid residues, or terephthalic acid derivatives, or a mixture thereof, and (b) a hydroxyl component comprising at least 90 mol% of ethylene glycol residues, with respect to 100 mol percent of the carboxylic acid component residues and 100 mol percent of the hydroxyl component residues in the polyester polymer, the particles having a degree The crystallinity is at least 25%, l t.V. is at least 0.77 dL/g, l t.V. at its surface and l t.V. at its center, wherein the l t.V. at the surface of the particles is not more than 0.15 dL/g higher than the l t.V. at the center of the particles, and the acetaldehyde level is 10 ppm or less.4 6. The particles of claim 45, wherein the particles comprise an aggregate having a volume of at least 1.0 m3.4 7. The particles of claim 46, wherein the l t.V. is the average of the difference between the l t.V. of the surface of the particles and the l t.V. of the center. of particles in the aggregate not more than 0.15 dL/m4. 8. Particles of claim 47, wherein the average l t.V. of the difference is not more than 0.10 dL/m4. 9. Particles of claim 48, wherein the average l t.V. is not more than 0.05 dL/m5. 0. Blow molded container obtained from the particles of claim 45.5. 1. A beverage bottle obtained from the particles of claim 45. 5. 2. A preform obtained from the particles of claim 45.