CN101921467B - Sulfonic acid compound-containing and tin compound-containing polylactic acid composition and preparation method thereof - Google Patents

Abstract

The invention discloses a sulfonic acid compound-containing and tin compound-containing polylactic acid composition and a preparation method thereof. The composition comprises polylactic acid, a sulfonic acid compound and a tin compound, wherein the sulfonic acid compound is one or more of dibasic sulfonic acid, polybasic sulfonic acid, a bibasic stannous sulfonate compound or a polybasic stannous sulfonate compound. The method for preparing the polylactic acid in the invention comprises the following steps of: performing dehydration treatment on lactic acid (or lactic acid prepolymer) serving as a raw material, and then performing melt polycondensation in the presence of a composite catalyst consisting of the dibasic sulfonic acid and/or the polybasic sulfonic acid and the tin compound to obtain the polylactic acid product; and the method also can comprise the following step of: further performing solid-phase polyreaction on the product of the melt polycondensation to finally obtain high molecular weight polylactic acid. Due to the adoption of the method, the reaction period is shortened by using a direct condensation method, and the polylactic acid having high molecular weight, high melting point and high thermal stability is obtained. For the polylactic acid prepared by the method, the process is simple and stable, the condensation time is shot, and the cost is relatively low.

Description

A kind of poly (lactic acid) composition that contains sulfoacid compound and tin compound and preparation method thereof

Technical field

The invention belongs to polymeric material field, be specifically related to a kind of poly (lactic acid) composition that contains sulfoacid compound and tin compound and a kind ofly utilize in dibasic sulfoacid or the polybasic sulfoacid one or more to prepare the method for poly(lactic acid) as composite catalyst with tin compound.

Background technology

Enter 21 century, environmental pollution and shortage of resources have become global problem, also more and more are subject to people's attention simultaneously.Synthesized polymer material take oil as raw material is widely used, and significant contribution has been made in the development of human civilization.But be difficult to behind this class materials'use recycle, cause at present serious " white pollution " problem; On the other hand, oil is Nonrenewable resources, and more and more a large amount of consumption makes the serious shortage of resources problem of facing mankind.People expect degradative plastics (mainly being aliphatic polyester), the especially research and development of the degradable material of renewable resources origin and use can greatly alleviate this two large problems in the near future.

Poly(lactic acid) (PLA) is a kind of degradable material that relatively many renewable resources origin are used at present research, it be the lactic acid that obtains take amylofermentation (or chemosynthesis) as basic raw material prepare a kind of to the nontoxic non-stimulated environment-friendly material of human body, it not only has good physicals, also has good biocompatibility and degradation property.The factor of restriction poly(lactic acid) widespread use mainly contains following two at present: one is that production cost is high, expensive; Another is to compare with general-purpose plastics, and the resistance toheat of poly(lactic acid) and anti-hydrolytic performance are all relatively poor.

Be shown below, at present poly(lactic acid) preparation method commonly used mainly can be divided into two kinds of ring-opening polymerization method (indirect method) and direct polycondensation methods (direct method):

(open loop) method is the polymerization route that present most applicability poly(lactic acid) adopts indirectly, namely at first dehydrating condensation between lactic acid molecules is made lactic acid oligomer, is generated the rac-Lactide of ring-type by the oligopolymer degraded again; Then the rac-Lactide ring-opening polymerization is generated superpolymer.This legal system standby and the polylactic acid molecule amount higher, better heat stability, second-order transition temperature and fusing point are all higher.Present maximum poly(lactic acid) manufacturer, the NatureWorks company of the U.S. utilize ring-opening polymerization to be prepared into the poly(lactic acid) of high molecular, now build 140,000 ton/years production equipment.But (open loop) method production technique is tediously long indirectly, and complex process is particularly repeatedly purified and recrystallization at lactide refined middle need, consumes a large amount of reagent, and high production cost has seriously hindered the widespread use of poly(lactic acid) as a kind of general-purpose plastics material.

In recent years, more and more caused people's concern by the method for acid through direct polycondensation by lactic synthesizing polylactic acid.Early report is arranged about the research of Direct Polycondensation of Polylactic Acid is external, recent year also begins to carry out the research of this respect.

Below we to the concise and to the point summary of carrying out of direct synthesis poly(lactic acid):

1. the principle of poly(lactic acid) direct condensation

The direct polymerization of poly(lactic acid) is a typical polycondensation, exists the balance of free lactic acid, water, oligopolymer and rac-Lactide in the reaction system, and its polymerization equation is as follows:

Calculation formula according to the polycondensation polymerized degree:

$\mathrm{DP}=\sqrt{\frac{K}{n_w}}$

Wherein: DP is the reactive polymeric degree, and K is reaction equilibrium constant; n _wBe residual moisture.

As can be seen from the above equation, at a certain temperature, because K is constant, therefore only have the content that reduces water molecules, just can reach the purpose that improves the polymerization degree, obtain the poly(lactic acid) than high molecular weight and fusing point.The method that is conducive to the eliminating of small molecules moisture is many, as increasing vacuum tightness, improves temperature and prolongs reaction times etc.Generally speaking, direct condensation is difficult to obtain the poly(lactic acid) of high molecular.Even if do not consider production efficiency and disregard into local time expand, regulate temperature and gas clean-up, only also be difficult to obtain molecular weight greater than 50,000 poly(lactic acid) by melt phase polycondensation.If its molecular weight is lower than 50,000, then owing to the inferior commercial value that loses of the properties of poly(lactic acid), thereby in the industrial direct polycondensation method scale operation poly(lactic acid) that also do not adopt.

Below just the different methods of the poly(lactic acid) direct condensation in the research and development do one and briefly introduce:

(1) melt phase polycondensation

Melt polymerization is to occur in the above polyreaction of melting point polymer temperature, is mass polymerization.Its advantage is that the product that obtains is pure, does not need separating medium, but the product relative molecular mass is not high, because along with the carrying out that reacts, the viscosity of system is increasing, small molecules is difficult to discharge, and balance is difficult to move to direction of polymerization.So rely on merely melt polymerization to be difficult to obtain having the poly(lactic acid) of higher molecular weight and fusing point.

(2) solution azeotropy method

The key of direct polycondensation of lactic acid is the discharge of water molecules, only has most water moleculess are discharged, and could obtain the product than high molecular weight.In polycondensation, use a kind of do not participate in polyreaction, can dissolve polymer organic solvent, under certain temperature and pressure, carrying out azeotropic with monomer lactic acid, water refluxes, phegma turns back in the reaction vessel through after dewatering, gradually micro-moisture contained in the reaction system is taken out of, driving a reaction carries out to direction of polymerization, thereby obtains the product of high molecular weight, Here it is solution azeotropy polymerization process.

At present, report that abroad the direct synthesizing polylactic acid of solution polymerization process is many, and obtained the product than high molecular weight, reached the requirement of practical application.But the defective of this method also is the solvent of the reaction system of introducing just.The higher solvent of boiling point that mostly adopts at present such as dimethylbenzene, phenyl ether, methyl-phenoxide, dibenzyl ether etc., all has larger toxicity, and one affects environment, and two also limit the application of resulting poly-lactic acid products.In addition, the use of a large amount of solvents has increased production cost greatly.Moreover the poly-lactic acid products fusing point that this method obtains only has about 166 ℃, and it is little 6～7 ℃ to obtain the PLA fusing point than open loop method.

(3) direct condensation+chain extending reaction

Because direct polycondensation of lactic acid is difficult to obtain the product than high molecular weight, people seek a kind of new method of obtaining poly-lactic acid in high molecular weight, and Here it is uses chainextender to process the oligopolymer of the poly(lactic acid) that direct condensation obtains, and obtains the poly(lactic acid) of high molecular.Can be used as the material of chainextender, majority is to have bifunctional or multi-functional highly active micromolecular compound.This method is same, and application to PLA brings problem because introduce some poisonous and harmful substances to participate in reaction as chainextender.In addition, the PLA fusing point that the chain extension method makes is lower, and degree of crystallinity is little even uncrystallizable.

(4) solid phase polymerization method

Solid state polymerization is that solid-state oligopolymer is higher than the polyreaction of carrying out under its second-order transition temperature being lower than melting point polymer, and this method can effectively improve the molecular weight of polyester polymer.

The mechanism of solid state polymerization is: at low-molecular-weight poly(lactic acid) performed polymer (section, powder etc.) by crystallization with functional group's terminal group, small molecule monomer and catalyzer enrichment in the pars amorpha, molecular balance is moved to positive dirction; By the decompression or rare gas element with reaction system small molecular product H ₂O takes away, so that molecular chain continues to increase, obtains the product of higher molecular weight.The solid state polymerization of poly(lactic acid) depends on the competition of chemical reaction and physical diffusion two aspects simultaneously, diffuses into Decompression atmosphere or atmosphere of inert gases through reversible chemical reaction, small molecules product from intraparticle diffusion to particle surface and then from particle surface.Determine principle according to low speed, the speed of reaction of whole polyreaction was determined by a slowest above-mentioned step.Polymerization time, polymerization temperature, catalyzer, vacuum tightness or inert gas flow, performed polymer degree of crystallinity, performed polymer geometrical shape etc. all will affect the process of solid-phase polymerization.

The fusing point of the poly(lactic acid) that employing direct method melting+solid state polymerization makes is not high, and the polymerization time of the polymerization technique that adopts is long yet up to the present.

2. the catalyzer of poly(lactic acid) direct condensation

Current direct polymerization mainly adopt tin compound as catalyzer or adopt tin compound with the sulfonic acid that only contains a sulfonic acid group as composite catalyst.Tin compound mainly is glass putty, tin protoxide, tin protochloride and stannous octoate.Sulfonic acid mainly contains tosic acid and methylsulfonic acid.

Ajioka etc. (Bull Chem Soc Jpn.68,2125,1995) have investigated nearly 20 kinds of metallic elements to the katalysis of lactic acid solution azeotropic polymerization, found that to only have the catalytic effect of tin compound more remarkable.Definite says, only has the poly(lactic acid) that could obtain high molecular when adopting tin and Bivalent Tin compound (tin protoxide, tin protochloride) after long-time polymerization.But the fusing point of products therefrom lower (163 ℃) is than low 5-7 ℃ of the fusing point of ring-opening polymerization products therefrom.

Japanese Patent P3436894 discloses tosic acid and tin protochloride and has been used as composite catalyst when coming the polymerization of catalysis lactic acid, can suppress significantly the coloring phenomenon that occurs in the polymerization process, thereby obtains the polymerisate of excellent quality.Kimura etc. (Polymer, 42,5059,2001) adopt tin protochloride/tosic acid as composite catalyst, have obtained the poly(lactic acid) of high molecular by melting/solid state polymerization technique.

Although adopt tin compound can obtain the poly(lactic acid) of high molecular as catalyzer or tin compound as composite catalyst with the sulfonic acid that only contains a sulfonic acid group, but for guaranteeing that polymerization velocity was unlikely to low, it is long that polymerization time is unlikely to, and generally all has to use larger catalyzer dosage.Such as (Polymer such as Kimura, 42,5059,2001) adopt the stannous chloride dihydrate (with respect to the lactic acid polymer) of 0.4wt% in the report, be converted into mol ratio [LA]/[Sn] of lactic acid monomer unit LA and tin atom Sn, then [LA]/[Sn]≤778.But being added in when guaranteeing polymerization velocity of a large amount of metal catalysts also aggravated side reaction (such as racemization, degraded etc.), thereby caused the fusing point of products therefrom not high, the low and color and luster of thermal stability deteriorated.Only contain a sulfonic acid group sulfoacid compound although add, such as methylsulfonic acid, ethyl sulfonic acid or tosic acid, can improve to a certain extent the color and luster of product and improve to a certain extent the fusing point of product, but the poor problem of the thermal stability of product still is not resolved.

Summary of the invention

For the equal relatively poor problem of the resistance toheat of poly(lactic acid) and anti-hydrolytic performance, the invention provides a kind of sulfoacid compound and tin compound of containing, the poly (lactic acid) composition with advantages such as high hydrolysis resistance performance, good color and luster and high-melting-points.

On the other hand, for the high problem of present stage poly(lactic acid) production cost, the invention discloses a kind of method of utilizing one or more the composite catalyst synthesizing polylactic acids that form with tin compound in dibasic sulfoacid or the polybasic sulfoacid.Preparing poly(lactic acid) by present method, to have a polymerization velocity fast, and products therefrom has the advantages such as high hydrolysis resistance performance, good color and luster and high-melting-point simultaneously.

Purpose of the present invention can reach by following measures:

Poly (lactic acid) composition

A kind of poly (lactic acid) composition that contains sulfoacid compound and tin compound, contain poly(lactic acid), sulfoacid compound and tin compound in the said composition, wherein sulfoacid compound is selected from one or more in dibasic sulfoacid, polybasic sulfoacid, dibasic sulfoacid tin compound, the polybasic sulfoacid tin compound.Contained dibasic sulfoacid refers to contain in the molecular formula two sulfonic group (SO in this composition ₃H) a large compounds; Polybasic sulfoacid refers to contain in the molecular formula sulfonic group (SO more than three or three ₃H) a large compounds.In addition, the present invention has no particular limits for their molecular structure.

Dibasic sulfoacid tin compound in this composition, polybasic sulfoacid tin compound can by directly add the dibasic sulfoacid tin compound in the composition, the polybasic sulfoacid tin compound obtains, also can add respectively dibasic sulfoacid, polybasic sulfoacid and tin compound and form dibasic sulfoacid tin compound, polybasic sulfoacid tin compound to composition and in composition.

The volatility of sulfoacid compound does not have the impact of matter to the performance of composition, brings variety of issue man-hour but consider that high volatile volatile may add at composition molding, with nonvolatile dibasic sulfoacid, polybasic sulfoacid or their tin compound for well.For organic volatility, academicly, industrial and legally various definitions is arranged and do not have a strict difinition unification or general.So be necessary in the present invention non-volatile sulfonic acid is described.In the present invention difficult or non-volatile dibasic sulfoacid, polybasic sulfoacid refer to preparation process be over after in composition its residual rate R% by element sulphur greater than 50% dibasic sulfoacid, polybasic sulfoacid.Be more preferably residual rate R% and be not less than 70%.Specific definition to residual rate R% elaborates in the aft section of invention again.

This composition has no particular limits the type of dibasic sulfoacid, polybasic sulfoacid, can be aromatic dibasic sulfoacid, aromatic polybasic sulfoacid or their tin compound, also can be the polybasic sulfoacid of aliphatic dibasic sulfoacid, aliphatics family or their tin compound, preferred nonvolatile aliphatic dibasic sulfoacid, polybasic sulfoacid or their tin compound.To the restriction that has nothing special of the carbonatoms in their molecular formula, but consider consistency with poly(lactic acid), then in their molecular formula number of carbon atom take 1-50 as well, be more preferably 1-30, best be 1-12.

Sulfoacid compound contains structure shown in the chemical formula (I) among the present invention,

Chemical formula (I)

Wherein x, y, z are the integer more than or equal to zero, and x+y 〉=2, z=0 when x=0; R is the hydrocarbon chain of C1-C30 or replaces hydrocarbon chain, is preferably the alkyl of C1-C30; M is tin element.Specifically, as x, when z equals zero, this compound is binary or polybasic sulfoacid, and when x, z were not equal to zero, this compound was binary or polybasic sulfoacid tin compound.In addition, the present invention has no particular limits for their molecular structure.But consider that sulfonate radical too much can affect the consistency of sulfoacid compound and polyester, x+y≤30 in general, preferred x+y≤10 most preferably are x+y≤5; Similarly, z≤30 in general, preferred z≤10 most preferably are z≤5.

When x+y=2, this compound is dibasic sulfoacid or dibasic sulfoacid tin compound; Wherein R is preferably the alkylidene group of C1-C20, the cycloalkylidene of C3-C20, the alkylene group of C3-C20, the inferior alkynyl group of C4-C20, the inferior alkynyl group of the replacement of the replacement cycloalkylidene of the substituted alkylene of C1-C20, C3-C20, the replacement alkylene group of C3-C20 or C4-C20.Specifically, R can be methylene radical, ethylidene, the propylidene of straight or branched, the butylidene of straight or branched, the pentylidene of straight or branched, the hexylidene of straight or branched, the inferior heptyl of straight or branched, straight or branched octylene, straight or branched nonamethylene, the inferior decyl of straight or branched, the inferior decyl of straight or branched, the inferior undecyl of straight or branched, the inferior dodecyl of straight or branched, the inferior tridecyl of straight or branched, the inferior tetradecyl of straight or branched, the inferior pentadecyl of straight or branched, the inferior hexadecyl of straight or branched, the inferior heptadecyl of straight or branched, the inferior octadecyl of straight or branched, the inferior nonadecyl of straight or branched, the perhaps inferior eicosyl of straight or branched; R also can be the substituted alkylene that contains at least one alkyl, cycloalkyl, amino, hydroxyl, alkoxyl group, carboxyl, ester group, acyl group, aldehyde radical, amide group, itrile group, nitro or halogen group; R also can be the cycloalkylidene of C3-C20 or the cycloalkylidene of replacement; R also can be the alkylene group that the alkylene group of the ethylene linkage C3-C20 that is in any position or the ethylene linkage that replaces are in the C3-C20 of any position.R can also be that acetylene bond is in the inferior alkynyl group of C4-C20 of any position or the acetylene bond that replaces is in the inferior alkynyl group of C4-C20 of any position.R is the alkylidene group of C1-C12 more preferably; The more preferably methylene-sulfonic acid of dibasic sulfoacid, ethionic acid, the third disulfonic acid, fourth disulfonic acid, penta disulfonic acid, own disulfonic acid, heptan disulfonic acid, hot disulfonic acid, the ninth of the ten Heavenly Stems disulfonic acid, the last of the ten Heavenly stems disulfonic acid, 1,11-undecane disulfonic acid, 1,12-dodecane disulfonic acid or 1,20-eicosane disulfonic acid; The more preferably methylene-sulfonic acid tin compound of dibasic sulfoacid tin compound, ethionic acid tin compound, the third disulfonic acid tin compound, fourth disulfonic acid tin compound, penta disulfonic acid tin compound, own disulfonic acid tin compound, heptan disulfonic acid tin compound, hot disulfonic acid tin compound, the ninth of the ten Heavenly Stems disulfonic acid tin compound, the last of the ten Heavenly stems disulfonic acid tin compound, 1,11-undecane disulfonic acid tin compound or 1,12-dodecane disulfonic acid tin compound.R further is preferably the alkylidene group of C3-C6.Dibasic sulfoacid further be preferably the third disulfonic acid, fourth disulfonic acid or 1,20-eicosane disulfonic acid; The dibasic sulfoacid tin compound further be preferably the third disulfonic acid tin compound, fourth disulfonic acid tin compound or 1,20-eicosane disulfonic acid tin compound.

When x+y 〉=3, this compound is polybasic sulfoacid or polybasic sulfoacid tin compound; Consider the consistency of they and monomer, oligopolymer and polyester, then in the molecular formula number of carbon atom take 3-50 as well, be more preferably 3-20, best be 3-12.Wherein, the inferior alkynyl group of the inferior cycloalkyl of the alkylidene of the preferred C3-C20 of R, C3-C20, the inferior alkenyl of C4-C20, C5-C20, the replacement time alkenyl of the replacement alkylidene of C3-C20, the replacement of C3-C20 time cycloalkyl, C4-C20 or the replacement time alkynyl group of C5-C20.Specifically, R can be propylidyne, the butylidyne of straight or branched, the pentylidyne of straight or branched, the hexylidyne of straight or branched, the inferior heptyl of straight or branched, the inferior octyl group of straight or branched, the inferior nonyl of straight or branched, the inferior decyl of straight or branched, the inferior decyl of straight or branched, time ten-the alkyl of straight or branched, the inferior dodecyl of straight or branched, the inferior tridecyl of straight or branched, the inferior tetradecyl of straight or branched, the inferior pentadecyl of straight or branched, the inferior hexadecyl of straight or branched, the inferior heptadecyl of straight or branched, the inferior octadecyl of straight or branched, the inferior nonadecyl of straight or branched, the perhaps inferior eicosyl of straight or branched; R also can be the replacement alkylidene that contains at least one alkyl, cycloalkyl, amino, hydroxyl, alkoxyl group, carboxyl, ester group, acyl group, aldehyde radical, amide group, itrile group, nitro or halogen group; R also can be the inferior cycloalkyl of C3-C20 or the inferior cycloalkyl of replacement; R also can be the inferior alkenyl that the inferior alkenyl of the ethylene linkage C4-C20 that is in any position or the ethylene linkage that replaces are in the C4-C20 of any position.R can also acetylene bond be in C5-C20 alkynyl group of any position or the acetylene bond that replaces is in C5-C20 alkynyl group of any position.R is the alkylidene of C3-C20 more preferably, further is preferably the alkylidene of C3-C12.

The total content of sulfoacid compound (does not comprise 0 by the quality of the sulphur atom among group-SO3-with 0-10000ppm in this composition, with respect to the poly(lactic acid) quality, lower with) for well, be 0-8000ppm preferably, 10-6000ppm more preferably, 100-5000ppm more preferably, 200-4000ppm more preferably is preferably 300-3000ppm again.Content is too small, then is difficult to guarantee its thermostability; The too high mechanical property that then can affect poly(lactic acid).

Tin compound in this composition can be in the mineral compound of the organic compound of tin monomer, tin and tin one or more.Specifically, tin compound can be the halogenide of tin, oxide compound, oxyhydroxide, carbonate, vitriol, nitrate, phosphoric acid salt, silicate, borate, oxymuriate, chromic salt, manganate, arsenate, cyanate, the alkyl carboxylate, alkyl dicarboxylic aid's salt, the alkyl multi-carboxylate, the substituted alkyl carboxylate salt, the substituted alkyl dicarboxylate, the substituted alkyl multi-carboxylate, the aromatic base carboxylate salt, the aromatic base dicarboxylate, the aromatic base multi-carboxylate, the substituted aromatic base carboxylate salt, the substituted aromatic base dicarboxylate, the substituted aromatic base multi-carboxylate, alkylsulfonate, the alkyl stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, the alkyl polysulfonate, substituted alkyl sulfonate, the substituted alkyl stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, the substituted alkyl polysulfonate, aromatic sulfonate, the aromatic base stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, the aromatic base polysulfonate, substituted aromatic base sulfonate, the substituted aromatic base stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, the substituted aromatic base polysulfonate, acetylacetonate, the alkyl alkoxide, substituted alkyl alkoxide etc.; The preferred of tin compound is the tin monomer, the halogenide of tin, the oxide compound of tin, the borate of tin, the alkyl carboxylate of tin, the substituted alkyl carboxylate salt of tin, alkyl dicarboxylic aid's salt of tin, the substituted alkyl dicarboxylate of tin, the alkyl multi-carboxylate of tin, the substituted alkyl multi-carboxylate of tin, the alkylsulfonate of tin, the alkyl stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate of tin, the alkyl polysulfonate of tin, the substituted alkyl sulfonate of tin, the substituted alkyl stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate of tin, the substituted alkyl polysulfonate of tin, the aromatic sulfonate of tin, the aromatic base stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate of tin, the aromatic base polysulfonate of tin, the substituted aromatic base sulfonate of tin, the substituted aromatic base stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate of tin, the substituted aromatic base polysulfonate of tin, the acetylacetonate of tin, the alkyl alkoxide of tin, the substituted alkyl alkoxide of tin; The more preferably tin of tin compound, tin protoxide, stannic oxide, tin protochloride, tin chloride, stannous acetate, stannous oxalate, stannous octoate, stannous citrate, stannous methanesulfonate, stannous fluoboric acid.

The total content of above-mentioned tin compound in poly (lactic acid) composition counted with 0-200000ppm with the tin element quality and (do not comprised 0, with respect to the poly(lactic acid) quality, lower same) for well, be 0-100000ppm preferably, more preferably 10-80000ppm is preferably 10-40000ppm.Content is too small, the situation of its hydrolytic resistance may occur being difficult to guarantee; The too high mechanical property that then may affect poly(lactic acid).

Poly (lactic acid) composition of the present invention has good anti-hydrolytic performance: when processing 5 days under 60 ℃, the condition of relative humidity 90%, the fall of the weight-average molecular weight of poly(lactic acid) is no more than 50%.Better be no more than 30%, best is no more than 10%.

In poly (lactic acid) composition of the present invention, in the scope of not damaging purpose of the present invention, can also contain nucleator, weather resisting agent, lubricant, releasing agent, fire retardant, dyestuff, antistatic agent, whipping agent etc.

The preparation method of poly (lactic acid) composition

The invention discloses a kind of method of utilizing one or more the composite catalyst synthesizing polylactic acid compositions that form with tin compound in dibasic sulfoacid or the polybasic sulfoacid.

The polymerization process of poly(lactic acid) direct condensation can be melting mass polymerization, solid state polymerization or their combination.Provide a kind of better method at this, namely by melt polymerization and solid state polymerization in conjunction with or formed by melt polymerization separately, its concrete steps are as follows:

Melt polymerization: under the inert gas or pressure be in the decompression situation of 0.1～50KPa, add in dibasic sulfoacid or the polybasic sulfoacid one or more and with the composite catalyst that tin compound forms lactic acid monomer or its oligopolymer carried out melt phase polycondensation 4～30h.

Solid state polymerization: the polyester prepolyer that melt phase polycondensation is obtained after crystallization treatment, under inert gas or pressure be to carry out 8～100 hours solid state polymerizations in the decompression situation of 0.05～2KPa.

In the process of polymerization, under inert gas or in the decompression situation, add dibasic sulfoacid or polybasic sulfoacid as catalyzer with lactic acid monomer polycondensation 4～30h.The melt polymerization temperature determines by polymerization single polymerization monomer and gained polyester product, for poly lactic acid polymerized temperature generally take 80-220 ℃ as good.The melt polymerization temperature is excessively low, and then polymerization velocity is low; The melt polymerization excess Temperature, then side reaction aggravation, painted intensification.Polymerization time is mainly decided on target molecular weight, but time oversize then product easy coloring, generally take 2-40 hour as good, preferred 4～30 hours.Adding to catalyzer does not have special requirement period, generally is incorporated as good after beginning with polymerization in 2 hours.By melt polymerization, the molecular weight of the poly(lactic acid) that obtains is determined by polymerizing condition, generally between several thousand to several ten thousand.The condensation of poly(lactic acid) is a reversible reaction with little equilibrium constant, and the later stage of melt condensation is because dehydration difficulty, and the rate of growth of molecular weight is very slow or do not increase, even owing to the existence of side reaction causes molecular weight and molecular weight.So generally be difficult to obtain the product of high molecular from melt condensation.

For poly(lactic acid), can adopt the molecular weight of the incompatible further raising poly(lactic acid) of solid polycondensation behind the melt polymerization.With the powder of melt polymerization product or particle through after the crystallization treatment under the inert gas or pressure be in the decompression situation of 0.05～2KPa, solid state polymerization 2～120 hours, wherein pressure progressively was down to 0.1～0.5KPa from normal pressure in 30～60 minutes.

The present invention has no particular limits the crystallization treatment of melt polymerization product.Can be that temperature with melt drops to isothermal crystal under a certain Tc, also each crystallization some time under the series of crystallization temperature; Can be crystallization under air atmosphere, under the nitrogen atmosphere, also can be crystallization under the vacuum, can also be in water or crystallization in other liquid mediums.Degree of crystallinity of the present invention also has no particular limits.Consider that from enrichment degree, inhibition particle or the powder bonded equal angles of end group then degree of crystallinity is more high better.But the too high meeting of degree of crystallinity reduces the activity of end group and reduces polymerization velocity.

The temperature of solid state polymerization determines by the second-order transition temperature of poly(lactic acid) and fusing point, that is the temperature of solid state polymerization (Ts) should be between second-order transition temperature (Tg) and fusing point (Tm):

Tg＜Ts＜Tm (5)

Be lower than second-order transition temperature, reaction can not be carried out.Being higher than fusing point then no longer is solid state polymerization.Because temperature is low, polymerization velocity is also low.To guarantee to improve polymerization temperature in the situation that particle or powder do not melt generally speaking as far as possible.Under the prerequisite greater than second-order transition temperature, preferably the temperature range of solid state polymerization be fusing point following 40 ℃ between the fusing point:

Tm-40＜Ts＜Tm (6)

Better the temperature range of solid state polymerization be fusing point following 20 ℃ between the fusing point:

Tm-20＜Ts＜Tm (7)

The temperature range of best solid state polymerization be fusing point following 10 ℃ between the fusing point:

Tm-10＜Ts＜Tm (8)

Because polymerization system molecular weight in polymerization process constantly increases, general degree of crystallinity also can improve constantly, so the fusing point of system also can constantly change in polymerization process.Fusing point can improve constantly generally speaking, and often is to improve comparatively fast at the initial stage, and the middle and later periods raising is slower even almost constant.So in polymerization process, it is constant that the temperature T s of polymerization can keep; Also can constantly change along with polymerisation run; Also can in the early stage Ts be remained on lower temperature, remain on moderate temperature mid-term and the later stage remains on comparatively high temps; Also can be in the early stage Ts be constantly adjusted and stage is constant at according to polymerisation run. a certain fixed temperature etc.

Because high molecular polymolecularity, high molecular melting has certain temperature range.So be necessary above-mentioned fusing point (or melt temperature) Tm is described.Heat-up rate when on the other hand, also being appreciated that the polymer fusing point and measuring has certain relation.Tm among the present invention refers to (10～20 ℃/min) the lower melt initiation temperature degree of measuring of medium heat-up rates.

Prepare the method for poly (lactic acid) composition for direct condensation of the present invention, the solid phase polymerization temperature scope that it adopts is 70～180 ℃, is 90～170 ℃ preferably.

Direct condensation of the present invention prepares the dibasic sulfoacid as catalyzer in the method for poly (lactic acid) composition and can be a kind of dibasic sulfoacid, also can be the mixture of two or more dibasic sulfoacids; In like manner, polybasic sulfoacid can be a kind of polybasic sulfoacid, also can be the mixture of two or more polybasic sulfoacids.The mixture of dibasic sulfoacid and polybasic sulfoacid can be one or more dibasic sulfoacid and the mixture of one or more polybasic sulfoacid.Same, the tin compound as catalyzer among the present invention can be a kind of tin compound, also can be the mixture of two or more tin compounds.

Among the preparation method of the present invention, as the dibasic sulfoacid of catalyzer or the volatility of polybasic sulfoacid effect of the present invention do not had substantial impact.But the too high meeting of the volatility of dibasic sulfoacid or polybasic sulfoacid brings following three problems:

A. because the time of polyester is generally longer, the too high meeting of volatility causes the decay of catalytic activity too fast, affects polymerization velocity;

B. to guarantee that polymerization velocity need to add a large amount of catalyzer, increase the cost of polymerization;

C. because sulfonic acid is strong acid, high-volatile dibasic sulfoacid or polybasic sulfoacid are had higher requirement to the erosion resistance of whole paradigmatic system as catalyzer.

In view of this, among the present invention take difficult volatility or non-volatility dibasic sulfoacid or polybasic sulfoacid as catalyzer as good.For organic volatility, academicly, industrial and legally various definitions is arranged and do not have a strict difinition unification or general.So be necessary in the present invention non-volatile sulfonic acid is described.In the present invention difficult or non-volatile dibasic sulfoacid, polybasic sulfoacid refer to polymerization be over after in polyester product its residual rate R% by element sulphur greater than 50% dibasic sulfoacid, polybasic sulfoacid.If do not contain other additives that do not add sulfur-bearing in element sulphur and the polymerization process in the polymerization single polymerization monomer, then the residual rate of dibasic sulfoacid or polybasic sulfoacid is defined by formula (1):

$R\%=\frac{m_{\mathrm{sp}}}{m_{s0}}\×100\%---\left(1\right)$

M in the formula _S0Be the catalyzer dibasic sulfoacid of polymerization process interpolation, the sulfonate radical-SO of polybasic sulfoacid origin ₃The quality of the element sulphur among the H; m _SpQuality for the element sulphur of sulfonate radical origin in the polyester product.

If under an element sulphur form with sulfonate radical existed in dibasic sulfoacid, the polybasic sulfoacid, then formula (1) can be expressed as:

$R\%=\frac{m_p\·C_{\mathrm{sp}}}{m_0\·C_{s0}}\×100\%---\left(2\right)$

Wherein: m ₀And m _pThe quality of products therefrom after the monomer mass that drops into when being respectively polymerization and the polymerization, C _S0And C _SpBe respectively polymerization when beginning with respect to the sulphur content in the products therefrom after the sulphur content of monomer and the polymerization.Definition observed yield Y% is:

$Y\%=\frac{m_p}{m_0}\×100\%---\left(3\right)$

Variable being changed to of formula (2) then:

$R\%=\frac{C_{\mathrm{sp}}}{C_{s0}}\×Y\%---\left(4\right)$

With the volatile evaluation index of residual rate as dibasic sulfoacid or polybasic sulfoacid, the residual rate of dibasic sulfoacid or polybasic sulfoacid was not less than 50% as good after then this polymerization process was finished take polymerization, was more preferably and was not less than 70%.

Described in the raw material such as composition among this preparation method, below be described further.Type to dibasic sulfoacid, polybasic sulfoacid catalyzer has no particular limits, and can be in binary aliphatic sulfonic acid, aliphatics polybasic sulfoacid, aromatic dicarboxylic sulfonic acid, the aromatic series polybasic sulfoacid one or more.But aromatic dicarboxylic sulfonic acid when poly lactic acid polymerized, polybasic sulfoacid acidity are stronger, easily make product painted, one or more in preferred aliphat dibasic sulfoacid, the aliphatics polybasic sulfoacid (being nonvolatile binary aliphatic sulfonic acid or nonvolatile aliphatics polybasic sulfoacid).To the restriction that has nothing special of the carbonatoms in their molecular formula.But consider the consistency of itself and poly(lactic acid), then in the molecular formula of dibasic sulfoacid the number of carbon atom take 1-50 as well, be more preferably 1-30, best be 1-12; In the molecular formula of polybasic sulfoacid the number of carbon atom take 3-50 as well, be more preferably 3-30, best be 1-12.

Among this preparation method as the dibasic sulfoacid of catalyzer for having general formula R ' (SO ₃H) ₂A large compounds, wherein R ' is preferably the alkylidene group of C1-C20, the cycloalkylidene of C3-C20, the alkylene group of C3-C20, the inferior alkynyl group of C4-C20, the inferior alkynyl group of the replacement of the replacement cycloalkylidene of the substituted alkylene of C1-C20, C3-C20, the replacement alkylene group of C3-C20 or C4-C20.Specifically, R ' can be from methylene radical, ethylidene, the propylidene of straight or branched, the butylidene of straight or branched, the pentylidene of straight or branched, the hexylidene of straight or branched, the inferior heptyl of straight or branched, straight or branched octylene, straight or branched nonamethylene, the inferior decyl of straight or branched, the inferior decyl of straight or branched, the inferior undecyl of straight or branched, the inferior dodecyl of straight or branched, the inferior tridecyl of straight or branched, the inferior tetradecyl of straight or branched, the inferior pentadecyl of straight or branched, the inferior hexadecyl of straight or branched, the inferior heptadecyl of straight or branched, the inferior octadecyl of straight or branched, the inferior nonadecyl of straight or branched, the perhaps inferior eicosyl of straight or branched; R ' also can be the substituted alkylene that contains at least one alkyl, cycloalkyl, amino, hydroxyl, alkoxyl group, carboxyl, ester group, acyl group, aldehyde radical, amide group, itrile group, nitro or halogen group; R ' also can be the cycloalkylidene of C3-C20 or the cycloalkylidene of replacement; R ' also can be the alkylene group that the alkylene group of the ethylene linkage C3-C20 that is in any position or the ethylene linkage that replaces are in the C3-C20 of any position.R ' can also be that acetylene bond is in the inferior alkynyl group of C4-C20 of any position or the acetylene bond that replaces is in the inferior alkynyl group of C4-C20 of any position.R ' is the alkylidene group of C1-C12 more preferably; The more preferably methylene-sulfonic acid of dibasic sulfoacid, ethionic acid, the third disulfonic acid, fourth disulfonic acid, penta disulfonic acid, own disulfonic acid, heptan disulfonic acid, hot disulfonic acid, the ninth of the ten Heavenly Stems disulfonic acid, the last of the ten Heavenly stems disulfonic acid, 1,11-undecane disulfonic acid, 1,12-dodecane disulfonic acid or 1,20-eicosane disulfonic acid; The more preferably methylene-sulfonic acid tin compound of dibasic sulfoacid tin compound, ethionic acid tin compound, the third disulfonic acid tin compound, fourth disulfonic acid tin compound, penta disulfonic acid tin compound, own disulfonic acid tin compound, heptan disulfonic acid tin compound, hot disulfonic acid tin compound, the ninth of the ten Heavenly Stems disulfonic acid tin compound, the last of the ten Heavenly stems disulfonic acid tin compound, 1,11-undecane disulfonic acid tin compound or 1,12-dodecane disulfonic acid tin compound.R ' further is preferably the alkylidene group of C3-C6.Dibasic sulfoacid further be preferably the third disulfonic acid, fourth disulfonic acid or 1,20-eicosane disulfonic acid; The dibasic sulfoacid tin compound further be preferably the third disulfonic acid tin compound, fourth disulfonic acid tin compound or 1,20-eicosane disulfonic acid tin compound.

Among this preparation method as the polybasic sulfoacid of catalyzer for having general formula R " (SO ₃H) ₃A large compounds; R " the alkylidene of preferred C3-C20, the inferior cycloalkyl of C3-C20, the inferior alkenyl of C4-C20, the inferior alkynyl group of C5-C20, the replacement time alkenyl of the replacement alkylidene of C3-C20, the replacement of C3-C20 time cycloalkyl, C4-C20 or the replacement time alkynyl group of C5-C20.Specifically, R " can be propylidyne; the butylidyne of straight or branched; the pentylidyne of straight or branched; the hexylidyne of straight or branched; the inferior heptyl of straight or branched; the inferior octyl group of straight or branched, the inferior nonyl of straight or branched, the inferior decyl of straight or branched, the inferior decyl of straight or branched, the inferior undecyl of straight or branched, the inferior dodecyl of straight or branched, the inferior tridecyl of straight or branched, the inferior tetradecyl of straight or branched, the inferior pentadecyl of straight or branched, the inferior hexadecyl of straight or branched, the inferior heptadecyl of straight or branched, the inferior octadecyl of straight or branched, the inferior nonadecyl of straight or branched, the perhaps inferior eicosyl of straight or branched; R " also can be the replacement alkylidene that contains at least one alkyl, cycloalkyl, amino, hydroxyl, alkoxyl group, carboxyl, ester group, acyl group, aldehyde radical, amide group, itrile group, nitro or halogen group; R " also can be the inferior cycloalkyl of C3-C20 or the inferior cycloalkyl of replacement; R " also can be the inferior alkenyl that the inferior alkenyl of the ethylene linkage C4-C20 that is in any position or the ethylene linkage that replaces are in the C4-C20 of any position.R " can also acetylene bond be in C5-C20 alkynyl group of any position or the acetylene bond that replaces is in C5-C20 alkynyl group of any position.R " alkylidene of C3-C20 more preferably, more advance-go on foot to be preferably the alkylidene of C3-C12.

Total add-on as dibasic sulfoacid, polybasic sulfoacid or their mixture of catalyzer among the preparation method of poly (lactic acid) composition of the present invention is pressed sulfonate radical SO ₃Among the H quality meter of sulphur atom with 0ppm-20000ppm (do not comprise 0, with respect to the quality of lactic acid monomer thing, lower with) for well, be 10-8000ppm better, be preferably again 100ppm-5000ppm, 200ppm-4000ppm more preferably, that best is 300-3000ppm.The too high degraded in mechanical properties that then easily causes product is crossed the low thermostability that then also affects product when affecting catalytic performance.

Can be in the mineral compound of the organic compound of tin monomer, tin and tin one or more as the tin compound of catalyzer among the preparation method of poly (lactic acid) composition of the present invention.Specifically, tin compound can be the halogenide of tin, oxide compound, oxyhydroxide, carbonate, vitriol, nitrate, phosphoric acid salt, silicate, borate, oxymuriate, chromic salt, manganate, arsenate, cyanate, the alkyl carboxylate, alkyl dicarboxylic aid's salt, the alkyl multi-carboxylate, the substituted alkyl carboxylate salt, the substituted alkyl dicarboxylate, the substituted alkyl multi-carboxylate, the aromatic base carboxylate salt, the aromatic base dicarboxylate, the aromatic base multi-carboxylate, the substituted aromatic base carboxylate salt, the substituted aromatic base dicarboxylate, the substituted aromatic base multi-carboxylate, alkylsulfonate, the alkyl stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, the alkyl polysulfonate, substituted alkyl sulfonate, the substituted alkyl stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, the substituted alkyl polysulfonate, aromatic sulfonate, the aromatic base stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, the aromatic base polysulfonate, substituted aromatic base sulfonate, the substituted aromatic base stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate, the substituted aromatic base polysulfonate, acetylacetonate, the alkyl alkoxide, substituted alkyl alkoxide etc.; The preferred of tin compound is the tin monomer, the halogenide of tin, the oxide compound of tin, the borate of tin, the alkyl carboxylate of tin, the substituted alkyl carboxylate salt of tin, alkyl dicarboxylic aid's salt of tin, the substituted alkyl dicarboxylate of tin, the alkyl multi-carboxylate of tin, the substituted alkyl multi-carboxylate of tin, the alkylsulfonate of tin, the alkyl stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate of tin, the alkyl polysulfonate of tin, the substituted alkyl sulfonate of tin, the substituted alkyl stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate of tin, the substituted alkyl polysulfonate of tin, the aromatic sulfonate of tin, the aromatic base stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate of tin, the aromatic base polysulfonate of tin, the substituted aromatic base sulfonate of tin, the substituted aromatic base stilbene-4,4'-bis-(1-azo-3, 4-dihydroxy-benzene)-2,2'-disulfonate of tin, the substituted aromatic base polysulfonate of tin, the acetylacetonate of tin, the alkyl alkoxide of tin, the substituted alkyl alkoxide of tin; The more preferably tin of tin compound, tin protoxide, stannic oxide, tin protochloride, tin chloride, stannous acetate, stannous oxalate, stannous octoate, stannous citrate, stannous methanesulfonate, stannous fluoboric acid.

Count with 0-200000ppm with the tin element quality as total add-on of the tin compound of catalyzer among the preparation method of poly (lactic acid) composition of the present invention and (do not comprise 0, quality with respect to the lactic acid monomer thing, lower with) for well, be 0-100000ppm preferably, more preferably 10-80000ppm is preferably 10-40000ppm.Content is too small, may affect catalytic performance and be difficult to guarantee its hydrolytic resistance; The too high mechanical property that then may affect polyester.

Lactic acid monomer can not done any processing in the method for preparing poly (lactic acid) composition of the present invention before polymerization; Also can be before polycondensation to the raw material pre-treatment of dewatering.Certainly, the dehydration here not only refers to the physics dehydration, also may relate to the condensation dehydration simultaneously.In this treating processes, no matter whether the existence of extra catalyst is arranged, condensation (polycondensation) may inevitably occur.

This preparation method and the poly(lactic acid) come has good anti-hydrolytic performance: when processing 5 days under 60 ℃, the condition of relative humidity 90%, the fall of the weight-average molecular weight of poly(lactic acid) is no more than 50%.Better be no more than 30%, best is no more than 10%.

This preparation method and the poly (lactic acid) composition that comes also has higher thermostability simultaneously, under the nitrogen gas stream of 100ml/min and temperature be under 200 ℃ the condition, its thermal weight loss speed is less than 0.1wt%/min, better less than 0.05wt%/min, in the time of preferably less than 0.005wt%.

In the scope of not damaging the object of the invention, can in this polymerization process, add various auxiliary agents, as: antioxidant, photostabilizer, painted inhibitor etc.

As the antioxidant that uses among the present invention, can enumerate sterically hindered phenol based compound, bi-ester of phosphite, sulfide compound etc.Example as the sterically hindered phenol based compound; can enumerate; Octadecane base-3-(3 '; 5 '-di-t-butyl-4 '-hydroxy phenyl) propionic ester; Octadecane base-3-(3 '-methyl-the 5 '-tertiary butyl-4 '-hydroxy phenyl) propionic ester; n-tetradecane base-3-(3 '; 5 '-di-t-butyl-4 '-hydroxy phenyl) propionic ester; 1; 6-hexylene glycol-two-[3-(3; the 5-di-tert-butyl-hydroxy phenyl) propionic ester]; 1; 4-butyleneglycol-two-[3-(3; the 5-di-tert-butyl-hydroxy phenyl) propionic ester]; 2; 2 '-methylene-bis-(4-methyl-tert-butyl phenol); triethylene glycol-two-[3-(the 3-tertiary butyl-5-methyl-4-hydroxy phenyl)-propionic ester]; four [methylene radical-3-(3 '; 5 '-di-t-butyl-4 '-hydroxy phenyl) propionic ester] methane; 3; 9-pair [2-{3-(3-tertiary butyl-4-hydroxy-5-aminomethyl phenyl) propionyloxy }-1; the 1-methylethyl] 2; 4; 8; 10-four oxaspiros (5; 5) undecane; N; N '-two-3-(3 '; 5 '-di-t-butyl-4 '-hydroxy phenyl) propionyl hexamethylene-diamine; N; N '-tetramethylene-two-3-(3 '-methyl-the 5 '-tertiary butyl-4 '-hydroxyl phenol) propionyl diamines; N; N '-two-[3-(3; 5-di-t-butyl-4-hydroxyl phenol) propionyl] hydrazine; N-salicylyl-N '-salicylidene hydrazine; 3-(N-salicylyl) amino-1; 2; the 4-triazole; N; N '-two [2-{3-(3,5-di-tert-butyl-hydroxy phenyl) propionyloxy } ethyl] oxyamide etc.Preferably: triethylene glycol-two-[3-(the 3-tertiary butyl-5-methyl-4-hydroxy phenyl)-propionic ester] and four [methylene radical-3-(3 ', 5 '-di-t-butyl-4 '-hydroxy phenyl) propionic ester] methane.As the phosphorous acid ester based compound, preferably at least 1 P-O bond is incorporated into the compound on the aromatic series base, as concrete example, can enumerate, three (2, the 4-di-tert-butyl-phenyl) phosphorous acid ester, four (2, the 4-di-tert-butyl-phenyl) 4,4 '-Ya biphenyl phosphinate, two (2, the 4-di-tert-butyl-phenyl) tetramethylolmethane-two-phosphorous acid ester, two (2,6-di-t-butyl-4-aminomethyl phenyl) tetramethylolmethane-two-phosphorous acid ester, 2,2-methylene-bis (4, the 6-di-tert-butyl-phenyl) octyl group phosphorous acid ester, 4,4 '-butylidene-two (3-methyl-6-tert butyl phenyl-two-tridecyl) phosphorous acid ester, 1,1,3-three (the 2-methyl-4-double tridecyl phosphorous acid ester-5-tertiary butyl-phenyl) butane, three (mixing single and two-nonyl phenyl) phosphorous acid ester, three (nonyl phenyl) phosphorous acid ester, 4, the different base of 4 '-Ya two (phenyl-dialkyl phosphites) etc., what can preferably use then is three (2, the 4-di-tert-butyl-phenyl) phosphorous acid ester, 2, the inferior different base two (4 of 2-, the 6-di-tert-butyl-phenyl) octyl group phosphorous acid ester, two (2,6-di-t-butyl-4-aminomethyl phenyl) tetramethylolmethane-two-phosphorous acid ester, four (2, the 4-di-tert-butyl-phenyl) 4,4 '-biphenylene phosphorous acid ester etc.

Concrete example as the thioether based compound, can enumerate dilauryl thiodipropionate, two-tridecyl thiodipropionate, myristyl thiodipropionate, two octadecyl thiodipropionate, tetramethylolmethane-four (3-lauryl thiopropionate), tetramethylolmethane-four (3-dodecyl thiopropionate), tetramethylolmethane-four (3-octadecyl thiopropionate), tetramethylolmethane-four (3-myristyl thiopropionate), tetramethylolmethane-four (the hard ester acyl of 3-thiopropionate) etc.

As the photostabilizer that uses among the present invention, can enumerate benzophenone based compound, benzotriazole based compound, aromatic series benzoic ether based compound, oxalic acid aniline based compound, cyanoacrylate based compound and bulky amine based compound etc.Concrete example as the benzophenone based compound, can enumerate, benzophenone, 2,4-dihydro benzophenone, 2,2 ', 4,4 '-tetrahydro-benzophenone, ESCALOL 567,2,2 '-dihydroxyl-4,4 '-dimethoxy-benzophenone, 2,2 '-dihydroxy benaophenonel, 2-hydroxyl-4-octyloxy benzophenone, 2-hydroxyl-4 dodecyl benzophenone, 2-hydroxyl-4-methoxyl group-5-diphenylsulfone ketone, 5-chlorine-2-hydroxyl benzophenone, 2,2 '-dihydroxyl-4,4 '-dimethoxy-5-diphenylsulfone ketone, 2-hydroxyl-4-methoxyl group-2 '-carboxyl benzophenone, 2-hydroxyl-4-(2-hydroxy-3-methyl-acryloxy isopropoxy benzophenone etc.

Concrete example as the benzotriazole based compound, can enumerate, 2-(2 '-hydroxyl-5 '-methyl-phenyl)-benzotriazole, 2-(2-hydroxyl-3,5-two-uncle-amyl group phenyl)-the 2H-benzotriazole, 2-(2 '-hydroxyl-3,5 '-two-tertiary butyl-phenyl) benzotriazole, 2-(2 '-hydroxyl-3 ', 5 '-two-tertiary butyl-5 '-methyl-phenyl) benzotriazole, 2-(2 '-hydroxyl-3 ', 5 '-two-tertiary butyl-phenyl)-5-chloro-benzotriazole, 2-(2 '-hydroxyl-3 ', 5 '-two-uncle-isopentyl-phenyl) benzotriazole, (2-hydroxyl-5-tert-butyl-phenyl) benzotriazole, 2-[2 '-hydroxyl-3 ', 5 '-two (α, α-dimethylbenzyl) phenyl] benzotriazole, 2-[2 '-hydroxyl-3 ', 5 '-two (alpha, alpha-dimethylbenzyl) phenyl]-the 2H-benzotriazole, 2-(2 '-hydroxyl-4 '-octyloxyphenyl) benzotriazole etc.

As the concrete example of aromatic series phenylformic acid based compound, can enumerate the alkyl phenyl salicylate classes such as p-tert-butyl-phenyl salicylate, p-octyl phenyl salicylate.

As the concrete example of oxalic acid amino benzenes compounds, can enumerate 2-oxyethyl group-2 '-ethyl oxalic acid dianiline, the 2-oxyethyl group-5-tertiary butyl-2 '-ethyl oxalic acid dianiline, 2-oxyethyl group-3 '-dodecyl oxalic acid dianiline etc.

As the concrete example of cyanoacrylate based compound, can enumerate ethyl-2-cyano group-3,3 '-phenylbenzene-acrylate, 2-ethylhexyl-2-cyano group-3,3 '-phenylbenzene-acrylate etc.

As the concrete example of bulky amine based compound, can enumerate 4-acetoxyl group-2,2,6,6-tetramethyl piperidine, 4-stearoyl-oxy-2,2,6,6-tetramethyl piperidine, 4-acryloxy-2,2,6,6-tetramethyl piperidine, 4-(phenylacetyl oxygen base)-2,2,6,6-tetramethyl piperidine, 4-benzoyloxy-2,2,6,6-tetramethyl piperidine, 4-methoxyl group-2,2,6,6-tetramethyl piperidine, 4-stearoyl-oxy-2,2,6, the 6-tetramethyl piperidine, 4-cyclohexyloxy-2,2,6, the 6-tetramethyl piperidine, 4-benzyloxy-2,2,6,6-tetramethyl piperidine, 4-phenoxy group-2,2,6,6-tetramethyl piperidine, 4-(ethylamino methanoyl)-2,2,6, the 6-tetramethyl piperidine, 4-(cyclohexyl carboxyamide oxygen base)-2,2,6, the 6-tetramethyl piperidine, 4-(phenyl amino methanoyl)-2,2,6,6-tetramethyl piperidine, two (2,2,6,6-tetramethyl--4-piperidyl)-carbonic ether, two (2,2,6,6-tetramethyl--4-piperidyl)-barkite, two (2,2,6,6-tetramethyl--4-piperidyl)-malonic ester, two (2,2,6,6-tetramethyl--4-piperidyl)-sebate, two (2,2,6,6-tetramethyl--4-piperidyl)-adipic acid ester, two (2,2,6,6-tetramethyl--4-piperidyl)-terephthalate, 1,2-two (2,2,6,6-tetramethyl--4-piperidyl oxygen)-ethane, α, α '-two (2,2,6,6-tetramethyl--4-piperidyl oxygen)-p-dimethylbenzene, two (2,2,6,6-tetramethyl--4-piperidyl cresylene-2, the 4-diurethanes, two (2,2,6,6-tetramethyl--4-piperidyl)-hexa-methylene-1, the 6-diurethanes, three (2,2,6,6-tetramethyl--4-piperidyl)-benzene-1,3,5-tricarboxylic ester, three (2,2,6,6-tetramethyl--4-piperidyl)-and benzene-1,3, the 4-tricarboxylic ester, 1-[2-{3-(3,5-two-tert-butyl-hydroxy phenyl) propionyloxy }-butyl]-4-[3-(3,5-two-tert-butyl-hydroxy phenyl) propionyloxy } 2,2,6, the 6-tetramethyl piperidine, 1,2,3,4-BTCA and 1,2,2,6,6-pentamethyl--4-piperidine alcohols and β, β, β ', β '-tetramethyl--3,9-[2,4,8,10-, four oxaspiros (5,5) undecane] condenses etc. of ethylene glycol.

The poly (lactic acid) composition that contains sulfoacid compound and tin compound of the present invention, by the synergy between sulfoacid compound and the tin compound, anti-hydrolytic performance is good, thermostability is high so that composition has simultaneously, colory advantage.With respect to tin compound/monobasic sulfonic acid composite catalyst, adopt tin compound/binary provided by the invention, polybasic sulfoacid composite catalyst to be aggregated in when guaranteeing polymerization activity the products therefrom thermostability is significantly improved; With respect to binary, polybasic sulfoacid catalyzer, composite catalyst of the present invention can make the products therefrom hydrolytic resistance significantly improve when guaranteeing polymerization activity, and color and luster is greatly improved.The present invention has the advantage of aforementioned two kinds of methods concurrently and without corresponding shortcoming, so that the performance of the range of application of poly(lactic acid) and the finished product all is greatly improved.Simultaneously provided by the inventionly prepare at short notice the method for poly-lactic acid in high molecular weight composition by the direct condensation of lactic acid with one or more composite catalysts with the tin compound composition in dibasic sulfoacid, the polybasic sulfoacid, make direct condensation prepare the method for aliphatic poly lactic acid in the industrial possibility that becomes.The method can shorten reaction time, has obtained to have simultaneously high hydrolytic resistance, high molecular, colory poly(lactic acid).Prepare poly(lactic acid) by the present invention, its technique simple and stable, polymerization time are short, cost is relatively cheap and product is pure etc.

Embodiment

The invention will be further described below in conjunction with embodiment, but this does not illustrate that the present invention only limits to these embodiment.

For being described as follows of the test that the present invention relates to:

Weight-average molecular weight (Mw), the Japanese Shimadzu LCsolution GPC of company, 30 ℃, chromatographic grade tetrahydrofuran (THF) leacheate, PS standard.

Fusing point (Tm), the DSC Q-100 of U.S. TA company.Sample is 200 ℃ of meltings after 2 minutes, at the speed borehole cooling to 0 of 20 ℃/min ℃, is warmed up to 200 ℃ again under 0 ℃ of speed with 20 ℃/min.Tm determines that by this heating curve its value is the thermal spike of melting peak.

Hydrolysis, the GL-04KA of Guangzhou Espec Environmental Equipment Co., Ltd type climatic chamber, 60 ℃, processed 5 days under 90% relative humidity, measure the weight-average molecular weight that is hydrolyzed the front and back poly(lactic acid) with GPC, calculated the range of decrease of weight-average molecular weight by the molecular weight of front and back.

Thermal destruction speed (thermal weight loss speed), U.S. TA company's T GA-Q100.Under the 100ml/min nitrogen gas stream, 200 ℃ of lower isothermals record.

Sulphur content is through AQF-100 (Mitsubishi chemistry) combustion method pre-treatment, by IC (ICS-2000, Dionex) quantitative assay.

Tin content obtains according to add-on, poly lactic acid polymerized calculation of yield, in the mass percent (ppm) of tin element quality with respect to poly(lactic acid).

Embodiment 1:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add 4952mg tin (add-on take metallic element with respect to the lactic acid quality as 27513ppm, lower with), (add-on is with sulfonate radical-SO for methylene-sulfonic acid 3964mg ₃Element sulphur quality meter is 8000ppm with respect to the lactic acid quality among the H, and is lower same).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 69%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:12.6 ten thousand.Fusing point Tm:165 ℃.Melt color and luster: little Huang.Thermal destruction speed: 1.06wt%/min.The molecular weight range of decrease after the hydrolysis: 15%.Sulphur content Csp:6261ppm in the product.The residual rate R%:54% of sulfonic acid catalyst.Metal content Cmp:39874ppm in the product.

Embodiment 2:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 9mg (25ppm), ethionic acid 338mg (632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 72%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:15.1 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.03wt%/min.The molecular weight range of decrease after the hydrolysis: 33%.Sulphur content Csp:702ppm in the product.The residual rate R%:80% of sulfonic acid catalyst.Metal content Cmp:35ppm in the product.

Embodiment 3:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 107.7mg (300ppm), the third disulfonic acid 765mg (1333ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 18 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 71%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:21.5 ten thousand.Fusing point Tm:170 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.01wt%/min.The molecular weight range of decrease after the hydrolysis: 27%.Sulphur content Csp:1821ppm in the product.The residual rate R%:97% of sulfonic acid catalyst.Metal content Cmp:423ppm in the product.

Embodiment 4:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous fluoboric acid (12976ppm), the third disulfonic acid 4049mg (7050ppm) of 5751mg.Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:23.9 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.75wt%/min.The molecular weight range of decrease after the hydrolysis: 25%.Sulphur content Csp:9875ppm in the product.The residual rate R%:98% of sulfonic acid catalyst.Metal content Cmp:18537ppm in the product.

Embodiment 5:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous methanesulfonate 132mg (281ppm) and Isosorbide-5-Nitrae-Ding disulfonic acid 818mg (1333ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 18 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:22.2 ten thousand.Fusing point Tm:169 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.03wt%/min.The molecular weight range of decrease after the hydrolysis: 20%.Sulphur content Csp:1885ppm in the product.The residual rate R%:99% of sulfonic acid catalyst.Metal content Cmp:402ppm in the product.

Embodiment 6:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannic oxide 134mg (587ppm) and 1,10-disulfonic acid in last of the ten Heavenly stems 1132mg (1333ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.1KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 69%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:17.4 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.18wt%/min.The molecular weight range of decrease after the hydrolysis: 19%.Sulphur content Csp:1922ppm in the product.The residual rate R%:99% of sulfonic acid catalyst.Metal content Cmp:851ppm in the product.

Embodiment 7:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add tin chloride 232mg (587ppm) and 5-hydroxyl-1,3,7-dodecane trisulfonic acid 1065mg (1333ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.1KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 68%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:22.9 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.15wt%/min.The molecular weight range of decrease after the hydrolysis: 37%.Sulphur content Csp:1958ppm in the product.The residual rate R%:100% of sulfonic acid catalyst.Metal content Cmp:863ppm in the product.

Embodiment 8:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous oxalate 94mg (300ppm) and inferior eicosyl disulfonic acid 1657mg (1333ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 69%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:12.3 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.07wt%/min.The molecular weight range of decrease after the hydrolysis: 22%.Sulphur content Csp:1937ppm in the product.The residual rate R%:100% of sulfonic acid catalyst.Metal content Cmp:435ppm in the product.

Embodiment 9:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 100mg (280ppm) and 1,3-the third disulfonic acid 363mg (632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 71%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:21.5 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.10wt%/min.The molecular weight range of decrease after the hydrolysis: 19%.Sulphur content Csp:876ppm in the product.The residual rate R%:98% of sulfonic acid catalyst.Metal content Cmp:395ppm in the product.

Embodiment 10:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 3mg (8.4ppm) and 1,3-the third disulfonic acid 6.32mg (11ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:6.7 ten thousand.Fusing point Tm:165 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.02wt%/min.The molecular weight range of decrease after the hydrolysis: 8%.Sulphur content Csp:15ppm in the product.The residual rate R%:99% of sulfonic acid catalyst.Metal content Cmp:12ppm in the product.

Embodiment 11:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous chloride dihydrate 103mg (300ppm) and 1,3-the third disulfonic acid 363mg (632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 69%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:19.1 ten thousand.Fusing point Tm:169 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.01wt%/min.The molecular weight range of decrease after the hydrolysis: 20%.Sulphur content Csp:908ppm in the product.The residual rate R%:99% of sulfonic acid catalyst.Metal content Cmp:435ppm in the product.

Embodiment 12:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous octoate 184mg (300ppm) and 1,5-naphthalene disulfonic acid 406mg (632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 68%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:19.4 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: little Huang.Thermal destruction speed: 0.10wt%/min.The molecular weight range of decrease after the hydrolysis: 18%.Sulphur content Csp:930ppm in the product.The residual rate R%:100% of sulfonic acid catalyst.Metal content Cmp:441ppm in the product.

Embodiment 13:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add 1,3-the third disulfonic acid 338mg (632ppm) and tin protoxide 306mg (1500ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.1KPa and pressure remained under the 0.1KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:15.1 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: colourless.Thermal destruction speed: 1.04wt%/min.The molecular weight range of decrease after the hydrolysis: 17%.Sulphur content Csp:624ppm in the product.The residual rate R%:69% of sulfonic acid catalyst.Metal content Cmp:2143ppm in the product.

Embodiment 14:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 107mg (300ppm) and 1,3-the third disulfonic acid 363mg (632ppm).Pour out after 5 hours (amounting to 30 hours) at (corresponding pressure at each temperature is 50KPa, 10KPa, 5KPa, 0.3KPa, 0.2KPa and 0.1KPa in turn) each melt polymerization under 120,140,160,180,200 and 220 ℃ subsequently and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 67%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:20.2 ten thousand.Fusing point Tm:168 ℃.Melt color and luster: little Huang.Thermal destruction speed: 0.02wt%/min.The molecular weight range of decrease after the hydrolysis: 19%.Sulphur content Csp:896ppm in the product.The residual rate R%:95% of sulfonic acid catalyst.Metal content Cmp:448ppm in the product.

Embodiment 15:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 107mg (300ppm) and 1,3-the third disulfonic acid 363mg (632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 1KPa.Pear shape bottle immersed in the silicone oil bath and oil bath temperature is raised to 90 ℃, 100 ℃, 110 ℃ and keeping at each temperature 1 hour in turn.(corresponding pressure at each temperature is 2KPa, 1KPa, 0.5KPa, 0.3KPa, 0.2KPa, 0.2KPa, 0.1KPa and 0.05KPa in turn) each solid state polymerization 12 hours under 130,140,150,155,160,162,164 and 166 ℃ amounts to solid state polymerization 96 hours subsequently.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:21.3 ten thousand.Fusing point Tm:170 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.02wt%/min.The molecular weight range of decrease after the hydrolysis: 17%.Sulphur content Csp:894ppm in the product.The residual rate R%:99% of sulfonic acid catalyst.Metal content Cmp:428ppm in the product.

Embodiment 16:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 107mg (300ppm), tin protochloride 61mg (300ppm) and 1,3-the third disulfonic acid 363mg (632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 71%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:22.1 ten thousand.Fusing point Tm:170 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.11wt%/min.The molecular weight range of decrease after the hydrolysis: 20%.Sulphur content Csp:881ppm in the product.The residual rate R%:99% of sulfonic acid catalyst.Metal content Cmp:846ppm in the product.

Embodiment 17:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 53.5mg (150ppm), 1, the mixture of 3-the third disulfonic acid 363mg (632ppm) and 1,2,3-the third trisulfonic acid 505mg (632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:17.7 ten thousand.Fusing point Tm:170 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.01wt%/min.The molecular weight range of decrease after the hydrolysis: 22%.Sulphur content Csp:1770ppm in the product.The residual rate R%:98% of sulfonic acid catalyst.Metal content Cmp:214ppm in the product.

Embodiment 18:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 53.5mg (150ppm), 1, the mixture of 3-the third disulfonic acid 363mg (632ppm) and the own disulfonic acid 437mg of 1,6-(632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:20.9 ten thousand.Fusing point Tm:170 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.008wt%/min.The molecular weight range of decrease after the hydrolysis: 23%.Sulphur content Csp:1744ppm in the product.The residual rate R%:98% of sulfonic acid catalyst.Metal content Cmp:211ppm in the product.

Embodiment 19:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ under the nitrogen gas stream of 100L/h, dewatered 2.5 hours.After adding stannous acetate 107mg (300ppm) and 1,3-the third disulfonic acid 363mg (632ppm), with system temperature rise to 160 ℃ and 160 ℃ with nitrogen gas stream under melt polymerization 6 hours, pour out, cool off and obtain the poly(lactic acid) prepolymer.10g prepolycondensate particle (particle diameter 1-3mm) is put into stainless-steel pipe (internal diameter 2cm, long 10cm), pass into the nitrogen gas stream (100L/h) that has heated from the steel pipe bottom.With steel pipe and nitrogen pipeline (long 3m) is put into oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 168 ℃ of solid state polymerizations 20 hours.Take out particle and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:20.0 ten thousand.Fusing point Tm:170 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.01wt%/min.The molecular weight range of decrease after the hydrolysis: 22%.Sulphur content Csp:895ppm in the product.The residual rate R%:99% of sulfonic acid catalyst.Metal content Cmp:428ppm in the product.

Comparative example 1:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 107mg (300ppm) and methylsulfonic acid 1440mg (2664ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:20.6 ten thousand.Fusing point Tm:169 ℃.Melt color and luster: colourless.Thermal destruction speed: 1.12wt%/min.The molecular weight range of decrease after the hydrolysis: 21%.Sulphur content Csp:571ppm in the product.The residual rate R%:15% of sulfonic acid catalyst.Metal content Cmp:429ppm in the product.

Comparative example 2:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add methylsulfonic acid 1440mg (2664ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 69%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:5.6 ten thousand.Fusing point Tm:163 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.02wt%/min.The molecular weight range of decrease after the hydrolysis: 16%.Sulphur content Csp:451ppm in the product.The residual rate R%:12% of sulfonic acid catalyst.

Comparative example 3:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add 1,3-the third disulfonic acid 363mg (632ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 70%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:21.1 ten thousand.Fusing point Tm:169 ℃.Melt color and luster: colourless.Thermal destruction speed: 0.009wt%/min.The molecular weight range of decrease after the hydrolysis: 79%.Sulphur content Csp:885ppm in the product.The residual rate R%:98% of sulfonic acid catalyst.

Comparative example 4:

After injecting the Pfansteihl aqueous solution 200g of 90wt% in the 500mL four-hole boiling flask, flask is put into oil bath.Install agitator at four-hole boiling flask, insert thermocouple thermometer, connect vacuum pipe and nitrogen pipeline also with behind the nitrogen replacement 3 times, oil bath temperature is risen to 120 ℃ dewater.System pressure progressively is reduced to 5KPa from normal pressure in the dehydration beginning 60 minutes; Under 5KPa, continue subsequently dehydration 1.5 hours (amounting to dehydration 2.5 hours); At this moment, with nitrogen system pressure is returned to normal pressure after, under nitrogen protection, add stannous acetate 107mg (300ppm).Then system temperature rises to 160 ℃, and pressure was progressively poured out after normal pressure is reduced to 0.3KPa and pressure remained under the 0.3KPa condition melt polymerization 4 hours (amounting to 6 hours) in 2 hours, and cooling obtains the poly(lactic acid) prepolymer.Be that the prepolycondensate powder 100g of 100-250um puts into behind the 1L pear shape bottle of Rotary Evaporators with nitrogen replacement 2 times with particle diameter, in 60 minutes, pressure dropped to 0.2KPa.Immerse pear shape bottle in the silicone oil bath and oil bath temperature is raised to 110 ℃ after kept 2 hours.Be warming up to subsequently 158 ℃ of solid state polymerizations 24 hours.Take out powder and obtain the poly(lactic acid) product.The observed yield Y% that weighing gets whole polymerization process is 65%.By the product sample is tested, obtain following salient features:

Weight-average molecular weight Mw:11.3 ten thousand.Fusing point Tm:166 ℃.Melt color and luster: colourless.Thermal destruction speed: 2.45wt%/min.The molecular weight range of decrease after the hydrolysis: 20%.

Table 1 embodiment and comparative example effect comparison table

Embodiment

Embodiment 1:

Embodiment 4:

Embodiment 7:

Embodiment 14:

Embodiment 15:

Embodiment 17:

Embodiment 19:

Comparative example 1:

Comparative example 2:

Polyester monocase and quality

90wt%L-lactic acid 200g

90wt%L-lactic acid 200g

90wt%L-lactic acid 200g

90wt%L-lactic acid 200g

90wt%L-lactic acid 200g

90wt%L-lactic acid 200g

90wt%L-lactic acid 200g

90wt%L-lactic acid 200g

90wt%L-lactic acid 200g

Sulfoacid compound and quality

Methylene-sulfonic acid 3964mg

1,3-the third disulfonic acid 4049mg

5-hydroxyl-1,3,7-dodecane trisulfonic acid 1065mg

1,3-the third disulfonic acid 363mg

1,3-the third disulfonic acid 363mg

1,3-the third disulfonic acid 363mg 1,2,3-the third trisulfonic acid 505mg

1,3-the third disulfonic acid 363mg

Methylsulfonic acid 1440mg

Methylsulfonic acid 1440mg

Sulfoacid compound add-on C s0/ppm

8000

7050

1333

632

632

1264

632

2664

2664

Tin compound and quality

Tin 4952mg

Stannous fluoboric acid 5751mg

Tin chloride 232mg

Stannous acetate 107mg

Stannous acetate 107mg

Stannous acetate 53.5mg

Stannous acetate 107mg

Stannous acetate 107mg

Nothing

Tin compound add-on C m0/ppm

27513

12975

587

300

300

150

300

300

-

Melt polymerization conditions

160℃*0.3KPa*6h

160℃*0.3KPa *6h

160℃*0.3KP a*6h

(120℃～ 220℃)* (50～ 0.1KPa)*30h

160℃*0.3K Pa*6h

160℃*0.3KPa *6h

160℃*N2* 6h

160℃*0.3KP a*6h

160℃*0. 3KPa*6h

Solid phase polymerization conditions

158℃*0.2KPa *24h

158℃*0.2KPa *24h

158℃*0.1KP a*24h

-

(90℃～ 160℃)*(2～ 0.05KPa) *96h

158℃*0.2KPa *24h

168*N2*20 h

158℃*0.2KP a*24h

158℃*0. 2KPa *24h

Observed yield Y%

69％

70％

68％

67％

70％

70％

70％

70％

69％

Weight-average molecular weight/ten thousand

12.6

23.9

22.9

20.2

21.3

17.7

20.0

20.6

5.6

The melt color and luster

Colourless

Colourless

Colourless

Little Huang

Colourless

Colourless

Colourless

Colourless

Colourless

Thermal destruction speed wt%/min

1.06

0.75

0.15

0.02

0.02

0.01

0.01

1.12

0.02

The weight-average molecular weight range of decrease after the hydrolysis

15％

25％

37％

19％

17％

22％

22％

21％

16％

Sulphur content Csp in the product a

6261

9875

1958

896

894

1770

895

571

451

The residual rate R% of sulfonic acid catalyst b

54％

98％

100％

95％

99％

98％

99％

15％

12％

Metal content/ppm

39874

18537

863

448

428

214

428

429

Nothing

Claims (14)

1. a poly (lactic acid) composition that contains sulfoacid compound and tin compound is characterized in that said composition contains poly(lactic acid), sulfoacid compound and tin compound; Wherein said sulfoacid compound is selected from one or more in non-volatile dibasic sulfoacid, polybasic sulfoacid, dibasic sulfoacid tin compound or the polybasic sulfoacid tin compound.

2. poly (lactic acid) composition according to claim 1 is characterized in that described sulfoacid compound is selected from one or more in binary aliphatic sulfonic acid, binary aliphatic sulfonic acid tin compound, aliphatics polybasic sulfoacid or the aliphatics polybasic sulfoacid tin compound.

3. each described poly (lactic acid) composition according to claim 1～2 is characterized in that carbonatoms is 1～30 in the described sulfoacid compound molecular formula.

4. each described poly (lactic acid) composition according to claim 1～2 is characterized in that described sulfoacid compound has the structure shown in the formula (I):

Wherein x, y or z are the integer more than or equal to zero, and x+y 〉=2; When x=0, z=0; R is the hydrocarbon chain of C1-C30 or replaces hydrocarbon chain that M is tin element.

5. poly (lactic acid) composition according to claim 1 is characterized in that the content of described sulfoacid compound in poly (lactic acid) composition is with group-SO ₃-middle element sulphur quality is counted 10ppm～10000ppm.

6. poly (lactic acid) composition according to claim 1 is characterized in that described tin compound is selected from one or more in tin protoxide, stannic oxide, tin protochloride, tin chloride, stannous acetate, stannous oxalate, stannous octoate, stannous methanesulfonate, the stannous fluoboric acid.

7. according to claim 1 or 6 described poly (lactic acid) compositions, it is characterized in that the total content of described tin compound in poly (lactic acid) composition count the 10ppm-40000ppm of poly(lactic acid) quality with the quality of tin element.

8. poly (lactic acid) composition according to claim 1, when it is characterized in that described poly (lactic acid) composition is processed 5 days under 60 ℃, the condition of relative humidity 90%, the fall of the weight-average molecular weight of poly(lactic acid) is no more than 50%.

9. preparation method who contains the poly (lactic acid) composition of sulfoacid compound and tin compound is characterized in that it comprises following steps A and step B or includes only steps A:

A) melt polymerization: under inert gas or pressure be in the decompression situation of 0.1～50KPa, take lactic acid, lactic acid oligomer or their composition as raw material, first after processed, add in non-volatile binary aliphatic sulfonic acid and the non-volatile aliphatics polybasic sulfoacid one or more with tin compound as composite catalyst in 120～220 ℃ of lower melt phase polycondensation 4～30h;

B) solid state polymerization: with the product of steps A under the inert gas or pressure be in the decompression situation of 0.05～2KPa, be to carry out 8～100 hours solid state polymerizations under 90～170 ℃ the condition in temperature.

10. method according to claim 9 is characterized in that the number of carbon atom in the molecular formula of described non-volatile binary aliphatic sulfonic acid is 1-30, and the number of carbon atom is 3-30 in the molecular formula of non-volatile aliphatics polybasic sulfoacid.

11. method according to claim 10 is characterized in that molecular formula the R ' (SO of described dibasic sulfoacid ₃H) ₂In R ' be the hydrocarbon chain of C1-C12 or replace hydrocarbon chain; The molecular formula of described polybasic sulfoacid is R " (SO ₃H) ₃, R wherein " be the hydrocarbon chain of C3-C20 or replace hydrocarbon chain.

12. method according to claim 9 is characterized in that total add-on of described dibasic sulfoacid, polybasic sulfoacid or their compositions is with sulfonate radical-SO ₃The quality of element sulphur is counted the 10ppm-8000ppm of lactic acid quality among the H.

13. method according to claim 9 is characterized in that described tin compound is selected from one or more in tin protoxide, stannic oxide, tin protochloride, tin chloride, stannous acetate, stannous oxalate, stannous octoate, stannous methanesulfonate, the stannous fluoboric acid.

14. method according to claim 9 is characterized in that total add-on of described tin compound counts the 10ppm-30000ppm of lactic acid quality with the tin element quality.