CN100473634C - Removal of color bodies from polytrimethylene ether glycol polymers - Google Patents

Abstract

Processes for reducing color in PO3G are provided. The processes include contacting PO3G with an activated carbon and then separating the PO3G from the activated carbon by, for example, filtration. The process provides PO3G having an APHA color less than that before contact with the absorbent. The processes are desirably used for polymers having a molecular weight of about 250 to about 5000.

Description

From the polytrimethylene ether glycol polymkeric substance, remove colour solid

Preference

The application requires the right of priority of United States Patent (USP) provisional application series number of submitting on May 6th, 2,003 60/468,226 and the United States Patent (USP) provisional application series number of submitting on August 5th, 2,003 10/634,687, and two pieces of patents all are incorporated herein for reference.

Invention field

The present invention relates to use solid adsorbent from polytrimethylene ether glycol, to remove colour solid.

Background of invention

1, ammediol (hereinafter being referred to as " PDO ") is that a kind of production multiple polymers that is applicable to comprises the monomer of polyester, urethane, polyethers and ring compound.The example that the homopolymerization of polytrimethylene ether glycol (hereinafter being referred to as " PO3G ") and copolyether are this base polymer.This base polymer finally is used for comprising fiber, film etc. in many application.

Generate 1, the chemical route of ammediol is known.For example, 1, ammediol can be prepared as follows:

1. catalytic epoxyethane (" hydroformylation route ") in the presence of phosphine, water, carbon monoxide, hydrogen and acid;

2. (" propenal route ") reduced in the catalytic solution phase hydration of propenal then.

Synthesize 1, these two lines of ammediol all relate to the centre of 3-hydroxy propanal (hereinafter also being referred to as " HPA ") and synthesize.In final catalytic hydrogenation step, HPA is reduced to PDO.Final purifying subsequently relates to several technologies, comprises vacuum distilling.

The raw material that biological and renewable resources such as maize raw material are originated from utilization generates 1, and the biochemical route of ammediol is existing to be described.Hereinafter this class PDO is called " biochemical PDO " or " biochemistry derive PDO ".For example, in such as klebsiella spp, Citrobacter, fusobacterium and lactobacillus species, found to be 1 with transformation of glycerol, the bacterial strain of ammediol.This technology has been disclosed in several the patents, comprises United States Patent (USP) 5,633,362,5,686,276, and nearest 5,821,092 interior, and all these patents all are incorporated herein for reference.At United States Patent (USP) 5,821, in 092, Nagarajan etc. disclose especially and have a kind ofly produced 1, the method for ammediol with the reorganization organism by glycerine is biological.This method is introduced with xenogenesis pdu dioldehydrase genetic modification and is had to 1 the narrow spectrum intestinal bacteria of 2-propylene glycol.The intestinal bacteria that change grow in the presence of as the glycerine of carbon source and isolate 1 from growth medium, ammediol.Because bacterium and yeast can both be converted into glycerine to glucose (as primverose) or other carbohydrate, so method of the present invention provide a kind of be applicable to produce polyester, polyethers and other polymkeric substance fast, cheap and eco-friendly 1, the ammediol monomer source.

From the 1980s, just used the precipitator method (for example using 1,2-propylene glycol and carboxylicesters or other material) that (odiferous) component of band look and band flavor is separated from required product (as enzyme) to obtain the purifying goods.Be settled out high molecular weight component from fermented liquid, it is known bleaching these components (DE 3917645) with reductive agent then.Find also that alternately micro-filtration nanofiltration then helps to remove residual compounds (EP 657529), wherein the high molecular weight material greater than size of separation is trapped.But the very fast obstruction of nano-filtration membrane and very expensive.

Disclose many treatment processs of removing existing look precursor among the PDO in the prior art, but these methods all are efforts and expensive, and can increase the cost of polymkeric substance.For example, a kind of purifying 1 that can be used as light polyester parent material, method of ammediol of providing is provided the United States Patent (USP) 5,527,973 of Kelsey.This method has several shortcomings, comprise using main equipment also need dilute with big water gaging, and shipwreck is to remove from product.The United States Patent (USP) 6,235,948 of Sunkara etc. discloses a kind of by preheating, preferably with heterogeneous acid catalyst such as perfluorinated ion-exchange polymer, from 1, removes the method for the impurity that adds lustre in the ammediol.The elimination catalyzer preferably isolates 1 by vacuum distillation method then, ammediol.APHA value by the polytrimethylene ether glycol of purifying glycol preparation is 30～40, but does not report the molecular weight of this polymkeric substance.

Polyalkylene ether glycols is generally by the acid-catalyzed dehydration of corresponding aklylene glycol or the acid catalysis open loop preparation of alkylene oxide.For example, polytrimethylene ether glycol can use soluble acid catalyst by making 1, ammediol dehydration or make the trimethylene oxide ring-opening polymerization and make.With method existing fully description among U.S. Patent Application Publication 2002/0007043 A1 and 2002/0010374 A1 that sulfuric acid catalyst prepares PO3G from glycol, it all is incorporated herein for reference.Be noted that the polyvalent alcohol synthesis condition determines the amount of the impurity, look precursor and the colour solid that form to a great extent.Polyether glycol by this method preparation will be used method known in the art purifying.The purification process of polytrimethylene ether glycol generally comprises (1) hydrolysing step so that formed acid esters hydrolysis between polymerization period, (2) the water extraction step is to remove acid catalyst, unreacted monomer, lower molecular weight linear oligomer and cyclic ethers oligopolymer, (3) alkaline purification, the general calcium hydroxide slurry of using, with the residual acid that neutralizes and precipitation exists, and polymkeric substance is dried and filtered in (4) to remove residuary water and solid.

As everyone knows, by 1, there are quality problems in the polytrimethylene ether glycol that the acid catalyzed polycondensation of ammediol generates, and especially color is industrial unacceptable.Polymer quality generally depends on the quality of starting material PDO.Except that starting material, the stability of polymerization process condition and polymkeric substance also has certain relation with variable color.Especially under the situation of polytrimethylene ether glycol, polyether glycol tends to band light color, and this is a unfavorable character in many end-uses.Polytrimethylene ether glycol is easy to by contacting with oxygen or air, and variable color especially at high temperature is so polymerization will be carried out under nitrogen atmosphere and polyether glycol will store in the presence of rare gas element.As additional preventive measures, add a small amount of suitable antioxidant.Preferred Yoshinox BHT (BHT, 2,6-di-t-butyl-4-cresols), concentration is about 100～500 μ g/g (microgram/gram) polyethers.

In addition, also once attempted reducing the color of polytrimethylene ether glycol, but do not obtain significant results with traditional method.For example, the United States Patent (USP) 2,520,733 of Morris etc. points out that the polytrimethylene ether glycol that is polymerized by PDO has special variable color tendency in the presence of acid catalyst.They have attempted several different methods but have failed to improve the color of polytrimethylene ether glycol, and method therefor comprises and uses gac, activated alumina, silica gel, diafiltration and hydrogenation separately separately.Therefore, they have developed a kind of to from 1, and ammediol prepared polyvalent alcohol in the presence of acid catalyst (2.5～6 weight %) and under about 175 ℃～200 ℃ temperature carries out the method for purifying.This purification process relates to allows the polymkeric substance diafiltration cross Fuller's earth, hydrogenation then.The purification process of this expansion makes the final product band light yellow, in fact, the colour of the polytrimethylene ether glycol that this method produced (embodiment XI wherein) only reduces to 8 and adds nail (unit of length) (Gardner) look, and this value is equivalent to the APHA value greater than 300, is not suitable for present requirement fully.

Mason is at United States Patent (USP) 3,326, disclose in 985 a kind of with the coupling vacuum stripping method at preparation molecular weight under the nitrogen in 1200～1400 scopes and have the polytrimethylene ether glycol that improves color, i.e. a method of the polytrimethylene ether glycol that molecular weight is lower.But colourity non-quantized and do not reach above requirement as yet.

Summary of the invention

The present invention discloses a kind of method that makes band look PO3G and sorbent material contact and separate PO3G and sorbent material subsequently that comprises, wherein PO3G with molecular weight after sorbent material contacts be about 250～about 5000, the APHA colour is less than about 50.

Detailed Description Of The Invention

Except as otherwise noted, all percentage ratios, umber, ratio etc. all are meant weight.

Trade(brand)name is represented with capitalization.

In addition, when an amount, concentration or other value or parameter provide with scope, preferable range or preferred upper limit value and preferred lower limit value inventory, be interpreted as particularly openly, whether disclose respectively regardless of these scopes by all scopes that form from any a pair of any upper range or preferred value and lower range and preferred value arbitrarily.

When using term " sorbent material ", be meant to be commonly used to remove the material that does not need component on a small quantity, no matter this removing by absorption or by absorbing, because many decoloring methods relate to two kinds of mechanism simultaneously.

Term " color " and " colour solid " be meant that existence can be used in that spectrophotometer in the visible-range quantizes with about 400～800nm wavelength and with the visible color of pure water comparison.Look precursor in PDO is sightless in this scope, but develops the color after polymerization.

The PO3G that makes from PDO of the present invention can be PO3G homopolymer or multipolymer.For example, PDO can aggregate into multipolymer with other glycol (hereinafter).Be applicable to PDO multipolymer of the present invention except containing 1, outside ammediol and/or its oligopolymer, also can contain the comonomer diol of 50 weight % at the most (preferred 20 weight % or still less).The comonomer diol that is applicable to present method comprises aliphatic diol, as ethylene glycol, 1, and 6-hexylene glycol, 1,7-heptanediol, 1,8-ethohexadiol, 1,9-nonanediol, decamethylene-glycol, 1,12-dodecanediol, 3,3,4,4,5,5-hexafluoro-1,5-pentanediol, 2,2,3,3,4,4,5,5-octafluoro-1,6-hexylene glycol, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10-ten hexafluoros-1,12-dodecanediol; Cycloaliphatic diol, as 1,4-cyclohexane diol, 1,4 cyclohexane dimethanol and the different two water sorbyl alcohols that take off; Polyol is as glycerine, TriMethylolPropane(TMP) and tetramethylolmethane.Preferred comonomer diol is selected from following one group: the 2-methyl isophthalic acid, ammediol, 2,2-dimethyl-1, ammediol, 2,2-diethyl-1, ammediol, 2-ethyl-2-(hydroxymethyl)-1, ammediol, 1,6-hexylene glycol, 1,8-ethohexadiol, decamethylene-glycol, different two water sorbyl alcohols and their mixture of taking off.If necessary, can add thermo-stabilizer, oxidation inhibitor and coloured material in polyblend or in the last polymkeric substance.

According to one aspect of the present invention, a kind of method comprises to be made band look PO3G and sorbent material contact and separates this PO3G and sorbent material subsequently, wherein PO3G with molecular weight after sorbent material contacts be about 250～about 5000 and the APHA colour less than about 50.Preferred APHA colour is less than about 40, is more preferably less than 30 and most preferably less than about 20.The APHA colour is measure (test method 1 sees below) as the color of ASTM-D-1209 definition.

The molecular weight of PO3G is about 250～about 5000.More preferably molecular weight is about 500～about 4000.Most preferably molecular weight is about 1000～about 3000.

According to another aspect of the present invention, sorbent material comprises at least a following material: gac, aluminum oxide, silicon-dioxide, diatomite, polynite, Fuller's earth, Gao Ling ore deposit and their derivative.Preferred adsorbent comprises gac.Term " gac " comprises " charcoal " herein.

Gac is a kind of have very big internal surface area and pore volume and amorphous solid very low with the avidity of water.The consumption of sorbent material depend on colour solid in the character, polytrimethylene ether glycol of sorbent material concentration, with the interaction and the processing condition of matrix, as duration of contact and temperature.For example, in practice of the present invention, in band look PO3G, adding based on polyether glycol weight 0.1～5% preferred 0.25～3% gac while stirring under inert atmosphere such as the nitrogen.

Contacting of PO3G and sorbent material is in a liquid state polymkeric substance and viscosity is low carries out under the temperature that is enough to allow to mix and stirs.Mixing and stirring can be carried out under preferred about 25～100 ℃ temperature at about 10 ℃～150 ℃.About 5～about 60min is carried out in contact, preferred about 10～about 30min.Preferred PO3G finishes under inert nitrogen atmosphere with contacting with filtration subsequently of sorbent material.

The method that is applicable to vacuum filtration is that those skilled in the art are known.Because the viscosity of PO3G is by at high temperature filtering accelerated filtration easily.Generally speaking, it is enough for the temperature in about 50 ℃～about 100 ℃ of scopes.For preparation on a small scale, CELPURE C65 filter bed is seated on the 1 μ m Whatman filter paper securely, load on the 250mL sintered glass funnel, and dispose the equipment of hot filtration apparatus.Other filtration medium also can use and be well-known to those skilled in the art, requires the fineness of strainer to be enough to hold back charcoal and is inert to glycol.

According to another aspect of the present invention, polytrimethylene ether glycol is being at least 50APHA with APHA colour before sorbent material contacts.Contact preceding colour with sorbent material and can be about 70～about 300.Contact preceding APHA colour with sorbent material and also can be about 85～250APHA or about 100～200APHA.

Can use interrupter method, wherein sorbent material be contacted effectively with polyvalent alcohol, and, as filter, centrifugal etc. polyvalent alcohol be separated with sorbent material by appropriate means after after a while by mixing.Method of the present invention also can be carried out in continuous or semicontinuous mode.For example, polyvalent alcohol pump from basin can be drawn fixed bed by sorbent material.Feed rate can be regulated by the kind of bed internal adsorption agent, consumption and previous use and the colourity of raw material, subtracts so that be long enough to the duration of contact of polyvalent alcohol and sorbent material make effluent to have required look.Effluent can keep a bit of time in containing jar, also can use immediately or transport.Other variable will be that those skilled in that art can recognize.

According to another aspect of the present invention, the APHA colour of polytrimethylene ether glycol is lowered about at least 50%.It is about at least 60% that the APHA colour of preferred polytrimethylene ether glycol is lowered, more preferably at least about 70%.

Method of the present invention also can be used for from the petrochemical industry source decolouring of the polytrimethylene ether glycol made as the PDO polymerization of using the preparation of propenal method, also is adapted to pass through the decolouring of the polyvalent alcohol that the PDO polymerization of biological path of preparing makes.

Activated carbon treatment can be carried out or just carry out before the filtration step of purifying process final polymkeric substance.Preferred method is just before final filtration step gac to be joined in the PO3G polymkeric substance, and stores this filtering polymkeric substance in the presence of antioxidant such as BHT.

It seems that used many carbon sources and form all be effective.Gac can be multi-form as powder, particle and shaping prod from many producers.Preferred form is a powdered active carbon.

The carbon of the multiple trade mark can use, and includes but not limited to Norit America G60, NORIT RO 0.8, Calgon PWA, BL and WPH, and Ceca ACTICARBONE ENO.Other form will be well-known to those skilled in the art.

According to another aspect of the present invention, a kind of method comprises:

(a) provide and comprise 1, the reactant of ammediol and polycondensation catalyst;

(b) the reactant polycondensation is become band look PO3G;

(c) this PO3G is contacted with sorbent material; And

(d) separate PO3G and sorbent material,

The color of PO3G wherein, with after sorbent material contacts, the APHA colour is less than about 50.Preferred APHA colour is more preferably less than 30 less than about 40, and most preferably less than about 20.Preferred adsorbent comprises gac, and PO3G contacts with gac based on the about 0.1～about 5 weight % of polytrimethylene ether glycol weight, and contact is carried out under about 10 ℃～about 150 ℃ temperature.

According to another aspect of the present invention, a kind of product comprises (i) band look PO3G and (ii) sorbent material (stating as this paper), and wherein the APHA colour of PO3G is less than about 50.Preferred APHA colour is about 40, more preferably from about 30, most preferably from about 20.Same preferred this product contains 0.25～about 5% sorbent material of having an appointment, more preferably from about 1%～about 3% sorbent material.

Material, equipment and test method

By 1, the PO3G polymkeric substance that ammediol is made is from E.I.Du Pont Company or can be from commercial sources.Gac (DARCO, CALGON and CECA) and BHT are from Aldrich Chemicals (Milwaukee WI).The CELPURE product from Advanced Minerals (Santa Barbara, CA).These products not only are used for removing the colour solid in the polymkeric substance, also play flocculating aids.

Test method 1. color measurenents and APHA value

Measure the color of polymkeric substance before and after solid adsorbent is handled with Hunterlab ColorQuest spectrophotometer [Reston, VA].The chromatic number of polymkeric substance is measured with APHA value (platinum-cobalt system) by ASTM D-1209.The molecular weight of polymkeric substance is calculated by the hydroxyl value that obtains by volumetry.

Embodiment

The following example provides for explanation the present invention, does not intend limiting the present invention.

The preparation of embodiment 1.PO3G

In a 22L glass reactor, add 13.9kg1, the ammediol and the 139g vitriol oil, then under nitrogen in 160 ℃ of these materials of polymerization, till reaching required number-average molecular weight.In general, the long reaction times provides the higher polymkeric substance of molecular weight.A part of crude polymer (5kg) and equivalent distilled water are shifted in another 22L glass reactor, under nitrogen covers, slowly stir this reaction mixture, be heated to 100 ℃ simultaneously, kept 4 hours.After 4 hours, allow this mixture cool down and be two-phase by gravity separation.Taking-up contains water and abandons it.Washing copolymer is once again for water.With the remaining sulfuric acid that exists in the excessive hydrogen calcium oxide and in the polymkeric substance.In decompression and 90 ℃ of down dry these polymkeric substance 3 hours, use the Whatman filter paper filtering that scribbles the CELPURE flocculating aids in advance then.Analyze the molecular weight and the color of gained purifying PO3G polymkeric substance.

Embodiment 2. is for alleviating the activated carbon treatment of polymer color

Assemble a 250mL sintered glass funnel safely.With CELPURE C65 (4.4g, 1.2kg/m ²) be seated in securely on the 1 μ m Whatman filter paper that places on the frit.Twine the heating zone around the funnel being the polymkeric substance heat supply during filtering.In a 250mL round-bottomed flask, put into PO3G (80g, MW=2400).In this polymkeric substance, add activated charcoal (0.008g, 0.01 weight %, DARCO G60).In polymkeric substance, add magnetic stirring bar, under the room temperature nitrogen atmosphere, on agitator, stir 10min then.Under covering, nitrogen this superpolymer is filtered by the sintered glass funnel then by indoor vacuum.By attemperation controller (VARIAC) temperature is set between 60 ℃～70 ℃.Final polymkeric substance is measured color on Hunterlab ColorQuest spectrophotometer.In polymkeric substance, add BHT (200 μ g/g polymkeric substance) after finishing immediately.The sample that does not add charcoal is compared measurement.The results are shown in table 1.

Embodiment 3-5

Use the method for the DARCO G60 activated charcoal repetition embodiment 2 of various amounts.The molecular weight of PO3G is 2170.The result also is shown in table 1.

The colour of table 1.PO3G and the relation of gac weight %

Embodiment	Gac weight %	Polymkeric substance colour APHA
			Contrast	0	126
2	0.01	121
			3	0.05	104
4	0.15	96
			5	0.25	88

Data in the table 1 show, activated charcoal has been removed colored foreign in the PO3G polymkeric substance and colour and has been increased to 0.25 weight % with the charcoal consumption from 0.01 weight % based on polymkeric substance and descends.

Embodiment 6-11

The method that repeats embodiment 5 is to determine the circulation ratio of this method.The molecular weight of used in these embodiments PO3G polymkeric substance is 2449, and colour is 145APHA and comprises 200 μ gBHT/g polymkeric substance.The results are shown in table 2.

The circulation ratio of table 2.PO3G color

Embodiment	Gac weight %	Colour APHA
			Contrast	0	145
6	0.25	106
			7	0.25	104
8	0.25	106
			9	0.25	109
10	0.25	107
			11	0.25	109

Data in the table 2 show that the look of use gac subtracts circulation ratio and is about ± 3APHA unit, and are suitable with the repeatability that single sample is measured.

Embodiment 12

In a 3-L filtration unit, use 2.5kg PO3G (MW=2170; Colour=126APHA) and 62.5g Darco G-60 gac repeat the method for embodiment 5.During the filtration,, each fraction is measured color, the results are shown in table 3 at difference moment collected polymer.

The look of table 3.PO3G subtracts, and is fairly large

PO3G	Colour APHA
		Before carbon is handled	126
First fraction	87
		Second fraction	88
Third stage branch	87
		Fourth stage branch	89

Embodiment 13-17

Use molecular weight be 2212 and colour be the PO3G polymkeric substance of 70APHA and relatively large carbon, repeat embodiment 5.

Table 4. carbon amount is to the influence of PO3G color

Embodiment	Gac weight %	Colour APHA	Change %
				Contrast	0	70	-
13	0.25	52	25.7
				14	1.0	42	40.0
15	2.0	39	44.3
				16	3.0	35	50.0
17	5.0	34	51.4

Filter polymkeric substance to separate carbon at 70 ℃.

Data in the table 4 show, when big (3 weight %), the color of polymkeric substance obviously improves about 50% to the carbon amount.

Embodiment 18

With crude polymer but not purified polymer repeats embodiment 5.The colour of crude polymer is 134APHA.This polymkeric substance is hydrolyzed, with excessive hydrogen calcium oxide neutralization and dry.In containing the dry PO3G of residual alkali and salt, add 0.25 weight % gac and filtration as mentioned above.Measure the colour of filtering PO3G, discovery is 80APHA, illustrates that gac can just add before the final filtration of purification step.

Embodiment 19-24

Use several different stages and form but consumption is fixed the activated charcoal of (2 weight %) and handled PO3G polymkeric substance (MW is 2070, and colour is 92APHA), the result is reported in the table 5.

Table 5

Embodiment	19	20	21	22	23	24
							Manufacturers	Norit America n	Norit America n	CALGON	CALGON	CALGON	CECA
Rank	DARCO- G60	NORIT RO0.8	PWA	BL	WPH	ACTICARBONE ENO
							The carbon form	Powder	The grain ball	Powder	Powder	Powder	Powder
The iodine number, mg/g	NA	1050	900	1000	800	NA
							The PO3G colour	52	77	56	61	53	48

The data of table 5 show that all powder carbon sample can both be reduced to 48-61 APHA to the colour of PO3G polymkeric substance from 92 effectively.

Claims (8)

1. method, comprise and make band look polytrimethylene ether glycol also separate polytrimethylene ether glycol and gac subsequently with the gac contact, be by polycondensation 1 in the presence of sulfuric acid catalyst wherein with the look polytrimethylene ether glycol, ammediol obtains, and wherein polytrimethylene ether glycol with molecular weight after gac contacts be 250～5000 and the APHA colour less than 50.

2. the process of claim 1 wherein that polytrimethylene ether glycol contacts with gac based on polytrimethylene ether glycol weight 0.1～5 weight %.

3. the method for claim 2 wherein contacts under 10 ℃～150 ℃ temperature and carries out.

4. the method for claim 3 wherein contacts and carries out 5～60min.

5. the process of claim 1 wherein that polytrimethylene ether glycol is being at least 50 with APHA colour before gac contacts.

6. the process of claim 1 wherein that the APHA colour is lowered at least 50%.

7. the method for claim 1, this method comprises the following step:

(a) provide and comprise 1, the reactant of ammediol and polycondensation catalyst;

(b) make the reactant polycondensation become band look polytrimethylene ether glycol;

(c) polytrimethylene ether glycol is contacted with gac; With

(d) separate polytrimethylene ether glycol and gac,

Wherein the color of polytrimethylene ether glycol is with after gac contacts, and the APHA colour is less than 50.

8. the method for claim 7, wherein polytrimethylene ether glycol contacts with gac based on polytrimethylene ether glycol weight 0.1～5 weight %, and this contact is carried out under 10 ℃～150 ℃ temperature.