CN101928386A - Method for preparing flame-retardant polyethylene glycol terephthalate - Google Patents
Method for preparing flame-retardant polyethylene glycol terephthalate Download PDFInfo
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- CN101928386A CN101928386A CN2009100874724A CN200910087472A CN101928386A CN 101928386 A CN101928386 A CN 101928386A CN 2009100874724 A CN2009100874724 A CN 2009100874724A CN 200910087472 A CN200910087472 A CN 200910087472A CN 101928386 A CN101928386 A CN 101928386A
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Abstract
The invention relates to a method for preparing flame-retardant polyethylene glycol terephthalate. The method comprises the following steps of: adding dimethyl terephthalate and ethylene glycol into untreated or uncalcined hydrotalcite for reaction according to a molar ratio of 1.0:1.5-2.2; controlling the reaction temperature to between 160 and 220 DEG C; and performing high-vacuum polycondensation at the temperature of between 260 and 290 DEG C and under the pressure to less than 150 Pa to obtain a polyethylene glycol terephthalate material with flame retardancy, wherein the amount of the hydrotalcite accounts for 0.1 to 10.0 percent of the weight of the dimethyl terephthalate; the particle size is 100nm to 50 mu m; and the calcination temperature of a hydrotalcite compound is between 250 and 700 DEG C. A polymerization result shows that a small amount of hydrotalcite makes the flame retardancy of the polyethylene glycol terephthalate excellent, and also has excellent catalytic effect, and the negative effect on the important processing properties of polyethylene synthesis such as molecular weight or the transparence of a finished product cannot change.
Description
Technical field:
The hydrotalcite original position that the present invention relates to a kind of flame retardant type polyethylene terephthalate is filled the also preparation method of catalyzed polymerization.The invention belongs to technical field of chemical engineering.
Background technology:
Polyethylene terephthalate (PET) is nineteen fifty-three to realize industrialized linear thermoplastic's polymkeric substance the earliest by Dupont company, PET can keep good physicals and mechanical property in relative broad range, its resistance to fatigue, rub resistance, ageing resistance excellence, electrical insulating property is outstanding, stable to most of organic solvents and mineral acid, PET is mainly as sheet material, fiber and beverage bottle.
Safe in utilization for ensureing the PET product, the flame retardant type polyester constantly is developed.The flame-retarded technology that uses mainly contains post-treatment technology, copolymerization, blending technology etc. at present.There is the unabiding shortcoming of flame retardant effect in the post-treatment technology.Blending technology is that the polyester of producing is carried out secondary processing, has increased production technique and cost.Copolymerization technique then needs to prepare the functional monomer with flame retardant properties, and its preparation process has increased the cost of product equally.
The synthesis material of PET is terephthalic acid (PTA) or dimethyl terephthalate (DMT) (DMT) and ethylene glycol (EG).The production process route of PET mainly contains two: the ester-interchange method of DMT and EG; The direct esterification method of PTA and EG.The compound of at present existing germanium, titanium, 3 kinds of elements of antimony is used for the catalyzer of industrial production PET, but tangible deficiency is all arranged, and the germanium series catalysts costs an arm and a leg; Titanium series catalyst makes PET jaundice, muddiness; Production of polyester producer adopts antimony-based catalyst mostly at present, mainly be antimonous oxide and antimony acetate, but the antimony-based catalyst activity is low, easily produce grey antimony in PET produces, and antimony is deleterious on physiology as a heavy metal species.
Hydrotalcite-based compound comprises hydrotalcite and houghite, and its main body generally is that the oxyhydroxide by two kinds of metals constitutes, and therefore is called laminated dihydroxy composite metal hydroxide (layered double hydroxides is abbreviated as LDH) again.The intercalation compound of LDH is called intercalated houghite.Hydrotalcite, houghite and intercalated houghite are referred to as hydrotalcite intercalation material (LDHs), its the most typical constitutional features is: the vertical ordered arrangement of the two-dimentional laminate of nanometer scale forms three-dimensional crystalline structure, its laminate metallic element is mainly magnesium and aluminium, is covalent bonding between atom; There is negatively charged ion in interlayer, with weak chemical bond, is connected with the main body laminate as ionic linkage, hydrogen bond etc.The laminate skeleton has positive charge, and interlayer anion is balance with it, and integral body presents electric neutrality.In addition, exist some water moleculess simultaneously at the oxyhydroxide interlayer, these water moleculess can be removed under the condition of not destroying laminate structure.The chemical constitution of hydrotalcite is generally:
Mg
2+ 1-xAl
3+ x(OH
-)
2A
N- X/nMH
2O, wherein A
N-Be n valency negatively charged ion.
Because of hydrotalcite has unique stratiform structural performance, thereby can be used as basic catalyst, redox catalyst and support of the catalyst.As: it can be used as catalyst for reaction such as hydrogenation, reformation, cracking, polycondensation, polymerization.Hydrotalcite contains a large amount of hydroxide radicals, and chloride superpolymer is had thermostability, and macromolecular material is had certain flame retardant resistance.
Recently hydrotalcite is found and can be used as the polycondensation catalyst use (US6,828,272 (2004), WO42335 (2004), WO014982 (2001)) for preparing PET.Publication number be LG-DOW Universal Tech. Corp. of CN1408001A in Chinese patents with [M (II)
1-xM (III)
x(OH)
2]
X+(A
N- X/n) mH
2The hydrotalcite that contains of O is the polycondensation catalyst system like the compound of thing structure, adopt direct esterification method route, with the 250ml flask is reactor, with ethylene glycol terephthalate (BHET) is that prepolycondensate has synthesized PET, and the fusing point of products obtained therefrom, limiting viscosity, acetaldehyde are compared with antimony acetate catalysis gained PET does not have big variation substantially.The Toufaili of Germany has studied the polymerization mechanism of the synthetic PET of hydrotalcite catalyzed BHET, think that catalytic activity gives (F.-A.El-Toufaili jointly by the interlayer anion of hydroxyl on the hydrotalcite and nucleophilicity, F.Ahmadnian, A.Dinse, G.Feix, K.-H.Reichert, Macromol.Mater.Eng., 2006,291,1136-1143; F.-A.El-Toufaili, G.Feix, K.-H.Reichert, Macromol.Mater.Eng., 2006,291,1144-1154).
Publication number is the Chinese patent of CN1587316, adopts direct esterification method route, is catalyzer with the antimony based compound, and polymerization is preceding with nano level hydrotalcite Mg
2+ 1-xAl
3+ x(OH
-)
2A
N- X/nMH
2O and PTA carry out intercalation processing earlier, carry out polycondensation then, synthesize the PET that limiting viscosity is 0.55dl/g to 1.05dl/g.Wang Ming carries out fusion intercalation with hydrotalcite, brominated flame-retardant and PET, finds that in the polymer processing moulding process, the spacing of hydrotalcite strengthens, and has formed intercalation configuration, has prepared the polyester composite with excellent fire-retardancy.
Summary of the invention:
The preparation method who the purpose of this invention is to provide a kind of easy and economic flame retardant type PET, employing has the hydrotalcite of cheapness of flame retardant efficiency and catalytic transesterification and polycondensation effect as the additive of the fire-retardant PET of ester-exchange technology path of preparing, original position fill synthetic have excellent flame retardancy can the PET product.
The hydrotalcite original position of flame retardant type polyethylene terephthalate of the present invention is filled also, and the step of preparation method's method of catalyzed polymerization is:
(1) dimethyl terephthalate (DMT) and ethylene glycol are prepared burden with the ratio of mol ratio 1.0: 1.5～2.2, add undressed again or the incinerating hydrotalcite, add reactor;
(2) above reaction mass is warming up to carries out transesterification reaction between 160～220 ℃, transesterification reaction 0.5～2.0 hour;
(3) amount that distillates by-product carbinol reaches theoretical amount 85% when above, transesterification reaction finishes, continue the high vacuum polycondensation phase, reactor is warming up to 260～290 ℃, being evacuated to pressure reduces to below the 150Pa, polycondensation 1.0～3.0 hours, discharging, the pet material that cooling obtains having flame retardant properties.
Described hydrotalcite molecular formula is Mg
1-xAl
x(OH)
2(CO
3)
X/2MH
2O (0＜x＜1, m=0～2), its amount ranges is 0.1～10.0% of a dimethyl terephthalate (DMT) quality, preferred 0.25～5.0%;
The particle size of described hydrotalcite is at 100nm～50 μ m;
The calcining temperature of described incinerating hydrotalcite compound is 250 to 700 ℃, is preferably 300 to 400 ℃.
The invention effect:
The present invention adopts domestic industry level Mg-Al carbonate type hydrotalcite original position to fill PET polycondensation raw material, and hydrotalcite had both been done fire retardant, served as the catalyzer of PET transesterify and polycondensation simultaneously again.Hydrotalcite is a kind of of layered double hydroxide, has nanometer laminated structure, make catalyzer with hydrotalcite, can realize in esterification and polycondensation process that dimethyl terephthalate (DMT) and glycol monomethyl are bulk diffusion to enter interlayer and react, realize that hydrotalcite is by the PET intercalation.Polymerization result is found, a spot of hydrotalcite not only makes the flame retardant properties of polyethylene terephthalate good, the catalytic effect excellence of while hydrotalcite, the transparency of polyester synthetic important process performance such as molecular weight or the finished product produces negative influence and does not change.
Embodiment
The following examples are to set forth rather than limit category of the present invention.Except as otherwise noted, all umber and percentage ratio all are that weight with DMT is benchmark among the embodiment.
Evaluation method
1.I.V. (dl/g): the limiting viscosity of polymer samples (I.V.) is under 30 ℃, uses mixing quality than being 60/40 the phenol and the solution of sym.-tetrachloroethane, measures strength of solution 0.1g/dL under 30 ℃ on Ubbelohde viscometer.
2. oxygen index: press the GB/T1454-1997 method and measure.
Embodiment 1
At one feed inlet and outlet is housed, nitrogen inlet, prolong adds in the 5L reactor of agitator and stirs and 1000 scattered gram DMT, 479 gram EG, the slurry of 2.5 gram hydrotalcites (particle size 100nm, unprocessed, DMT quality 0.25%).Rise to 194～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 270～280 ℃ of scopes, continue polycondensation 2.6 hours, finish polyreaction, discharging makes fire-retardant PET.
Embodiment 2
At one feed inlet and outlet is housed, nitrogen inlet, prolong, adding stirs and 1000 scattered gram DMT in the 5L reactor of agitator, 543 gram EG, the slurry of 7.50 gram hydrotalcites (particle size 50 μ m, 250 ℃ of calcination temperatures, DMT quality 0.75%).Rise to 191～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 270～280 ℃ of scopes, continue polycondensation 2.5 hours, finish polyreaction, discharging makes fire-retardant PET.
Embodiment 3
At one feed inlet and outlet is housed, nitrogen inlet, prolong adds in the 5L reactor of agitator and stirs and 1000 scattered gram DMT, 639 gram EG, the slurry of 5.0 gram hydrotalcites (particle size 1 μ m, 500 ℃ of calcination temperatures, DMT quality 0.50%).Rise to 192～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 270～280 ℃ of scopes, continue polycondensation 2.5 hours, finish polyreaction, discharging makes fire-retardant PET.
Embodiment 4
At one feed inlet and outlet is housed, nitrogen inlet, prolong adds in the 5L reactor of agitator and stirs and 1000 scattered gram DMT, 702 gram EG, the slurry of 30 gram hydrotalcites (particle size 3 μ m, 700 ℃ of calcination temperatures, DMT quality 3.0%).Rise to 185～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 270～280 ℃ of scopes, continue polycondensation 2.0 hours, finish polyreaction, discharging makes fire-retardant PET.
Embodiment 5
At one feed inlet and outlet is housed, nitrogen inlet, prolong adds in the 5L reactor of agitator and stirs and 1000 scattered gram DMT, 702 gram EG, the slurry of 50 gram hydrotalcites (particle size 10 μ m, 300 ℃ of calcination temperatures, DMT quality 5.0%).Rise to 180 ℃～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 270～280 ℃ of scopes, continue polycondensation 1.6 hours, finish polyreaction, discharging makes fire-retardant PET.
Embodiment 6
At one feed inlet and outlet is housed, nitrogen inlet, prolong adds in the 5L reactor of agitator and stirs and 1000 scattered gram DMT, 702 gram EG, the slurry of 30 gram hydrotalcites (particle size 10 μ m, 400 ℃ of calcination temperatures, DMT quality 3.0%).Rise to 185 ℃～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 260～270 ℃ of scopes, continue polycondensation 2.25 hours, finish polyreaction, discharging makes fire-retardant PET.
Embodiment 7
At one feed inlet and outlet is housed, nitrogen inlet, prolong adds in the 5L reactor of agitator and stirs, 1000 scattered gram DMT, 702 gram EG, the slurry of 1 gram hydrotalcite (particle size 10 μ m, 300 ℃ of calcination temperatures, DMT quality 0.1%).Rise to 194 ℃～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 270～280 ℃ of scopes, continue polycondensation 3 hours, finish polyreaction, discharging makes fire-retardant PET.
Embodiment 8
At one feed inlet and outlet is housed, nitrogen inlet, prolong adds in the 5L reactor of agitator and stirs and 1000 scattered gram DMT, 702 gram EG, the slurry of 100 gram hydrotalcites (particle size 10 μ m, 300 ℃ of calcination temperatures, DMT quality 10%).Rise to 160～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 280～290 ℃ of scopes, continue polycondensation 1 hour 50 minutes, finish polyreaction, discharging makes fire-retardant PET.
Comparative example 1
At one feed inlet and outlet is housed, nitrogen inlet, prolong, adding stirs and 1000 scattered gram DMT 702 gram EG, 0.15 gram Cobaltous diacetate, the slurry of 0.20 gram manganese acetate in the 5L reactor of agitator.Rise to 195～220 ℃ gradually from room temperature, fractionation capital temperature keeps 63～65 ℃, and the amount that distillates by-product carbinol in the question response still reaches theoretical amount 85% when above, adds 0.5 and restrain antimonous oxide in reactor, 0.2 gram trimethyl phosphite 99, begin decompression and heat up, pressure is reduced to below the 150Pa, and simultaneous temperature is raised in 280～290 ℃ of scopes, continue polycondensation 2 hours, finish polyreaction, discharging makes PET.
By experiment, proved and utilized in-situ polymerization, with the feasibility of hydrotalcite while as a kind of fire retardant and synthetic PET catalyzer.According to evaluation method products obtained therefrom is carried out performance test.The gained evaluation result as shown in Table 1 and Table 2.As can be seen: compare with commercial PET, talcum can promote the flame retardant properties of PET as a kind of good fire retardant significantly; Hydrotalcite is as a kind of PET synthetic catalyzer, and transesterify time and transesterification temperature in the reaction descend along with the increasing of addition of LDHs, illustrates that hydrotalcite has the selectivity of excellent catalytic activity reaction.
Polycondensation result under the different hydrotalcite content of table 1
| Sample | T ini/℃ | t t/min | [η]/(dlg+-1) |
| PET | 195 | 77 | 0.67 |
| LDH-0.25 | 194 | 70 | 0.69 |
| LDH-0.5 | 192 | 67 | 0.69 |
| LDH-0.75 | 191 | 63 | 0.67 |
| LDH-3 | 185 | 58 | 0.58 |
| LDH-5 | 185 | 58 | 0.55 |
Annotate: t
t: transesterify time, T
Ini: the initial temperature that methyl alcohol is steamed
The limiting oxygen index(LOI) of the hydrotalcite catalyzed PET of table 2
Claims (1)
1. the preparation method of a fire-retardant polyethylene terephthalate is characterized in that:
(1) dimethyl terephthalate (DMT) and ethylene glycol are prepared burden with the ratio of mol ratio 1.0: 1.5～2.2, more undressed or incinerating hydrotalcite are added reaction;
(2) above reaction mass is warming up to carries out transesterification reaction between 160～220 ℃, transesterification reaction 0.5～2.0 hour;
(3) amount that distillates by-product carbinol reaches theoretical amount 85% when above, transesterification reaction finishes, continue the high vacuum polycondensation phase, reactor is warming up to 260～290 ℃, being evacuated to pressure reduces to below the 150Pa, polycondensation 1.0～3.0 hours, discharging, the pet material that cooling obtains having flame retardant properties;
The hydrotalcite molecular formula is Mg
1-xAl
x(OH)
2(CO
3)
X/2MH
2O (0＜x＜1, m=0～2), its amount ranges is 0.1～10.0% of a dimethyl terephthalate (DMT) quality;
Particle size is at 100nm～50 μ m.;
The calcining temperature of hydrotalcite compound is 250～700 ℃.
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|---|---|---|---|
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| CN101928386B CN101928386B (en) | 2012-05-30 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106893274A (en) * | 2017-03-27 | 2017-06-27 | 山东本源晶体科技有限公司 | A kind of preparation method of silicon phosphorus cooperative flame retardant graphene polymer material |
| CN110358266A (en) * | 2019-07-29 | 2019-10-22 | 常州大学 | A kind of synthesis of cerium oxide modification aluminium titanium hydrotalcite and its preparation method of modified flame-retardant PET material |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1139678A (en) * | 1995-07-04 | 1997-01-08 | 天津石油化工公司涤纶厂 | Production method of polyester for high-transparency ultra-thin film |
| CA2395051A1 (en) * | 1999-12-10 | 2001-06-14 | Jens-Peter Wiegner | Catalyst systems for polycondensation reactions |
| CN1277870C (en) * | 2004-07-09 | 2006-10-04 | 浙江大学 | Process for preparing polyethylene glycol terephthalate/nano hydrotalcite composite |
-
2009
- 2009-06-22 CN CN2009100874724A patent/CN101928386B/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106893274A (en) * | 2017-03-27 | 2017-06-27 | 山东本源晶体科技有限公司 | A kind of preparation method of silicon phosphorus cooperative flame retardant graphene polymer material |
| CN106893274B (en) * | 2017-03-27 | 2018-03-30 | 山东本源晶体科技有限公司 | A kind of preparation method of silicon phosphorus cooperative flame retardant graphene polymer material |
| CN110358266A (en) * | 2019-07-29 | 2019-10-22 | 常州大学 | A kind of synthesis of cerium oxide modification aluminium titanium hydrotalcite and its preparation method of modified flame-retardant PET material |
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|---|---|
| CN101928386B (en) | 2012-05-30 |
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