CN105086392B - A kind of polydactyl acid and preparation method thereof - Google Patents
A kind of polydactyl acid and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a kind of polydactyl acid, it is the melt blended material of following components：Component a. star polyalcohols esters；Component b. linear polylactic acids；With component c. alkene and the copolymer of unsaturated acid anhydride.According to the present invention, the copolymer reaction in-situ of multi-arm star polyalcohols ester (such as star PBS) and composition c forms cross-linked structure.The toughness of resulting polydactyl acid is significantly improved, with elongation at break very high；And can obtain the controllable polydactyl acid of toughness by adjusting the branched structure of star polyalcohols ester (such as star PBS) and the content of star polyalcohols ester (such as star PBS) and the copolymer.
Description
Technical field
The present invention relates to poly-lactic acid material field, and in particular to a kind of polydactyl acid with preferable toughness.The present invention
Further relate to the preparation method of above-mentioned polydactyl acid
Background technology
The substantial amounts of production of synthesis macromolecular material and using generating two key subjects：Limited petroleum resources it is a large amount of
Environmental pollution caused by consumption and waste polymer.In this case, environment-friendly biodegradation material arises at the historic moment simultaneously
Flourished.In numerous biodegradated polymer materals developed, PLA (PLA) is with renewable resource plant
It is raw material, it is nontoxic, it is nonirritant, with excellent biocompatibility, bioresorbable, complete biodegradability, while
Also there is excellent physics, mechanical performance, thus more and more widely paid close attention to.But, current commercialization polylactic acid melt
Low intensity, fragility are high, toughness is not enough, low the having become of elongation at break hinders the key technology of PLA development and application to ask
Topic.
The content of the invention
In view of the shortcomings of the prior art, the invention provides a kind of polydactyl acid, the melt of the polydactyl acid glues
Degree is low, it is easy to machine-shaping；On the premise of mechanical performance is ensured, the polydactyl acid has preferable toughness, with higher
Elongation at break.
According to an aspect of the invention, there is provided a kind of polydactyl acid, it is the melt blending comprising following components
Thing：
Component a. star polyalcohols esters；
Component b. linear polylactic acids；With
The copolymer of component c. alkene and unsaturated acid anhydride.
In above-mentioned polydactyl acid, the number-average molecular weight of preferably described star polyalcohols ester is 500~30000；It is preferred that institute
The weight average molecular weight for stating linear polylactic acid is 10~400,000.
In one embodiment of above-mentioned polydactyl acid, the amount of the component a account for polydactyl acid total amount 2~
30wt%, preferably 2~10wt%.The addition of the star polyalcohols ester can be effectively reduced the melt viscosity of polydactyl acid,
Star polyalcohols ester contains the fragility that multiple methylene based structures are conducive to the common linear PLA of improvement.Star polyalcohols ester can be two
First alcohol and binary acid and the polymer of a small amount of polyalcohol.For example, component a may be selected from star polyethylene glycol succinate, star
Shape poly butylene succinate, star poly-succinic hexylene glycol ester, star polyadipate ethylene glycol, star polybutyleneadipate
At least one in ester and star polyadipate hexylene glycol ester.In a specific embodiment, the component a is the poly- fourth of star
Succinate adipate (PBS).
In another embodiment of above-mentioned polydactyl acid, acid anhydrides in hydroxyl in the component a and component c rubs
You are than being 1:1~8.The presence of excessive anhydride bond has beneficial to the crosslink density for improving polydactyl acid.
In another embodiment of above-mentioned polydactyl acid, the structural formula of the copolymer in preferably described component c is
In formula, R is containing the 1-30 alkyl of carbon atom, preferably containing the alkyl of 6-20 carbon atoms, 1≤n≤100.It is described common
The side chain with side chain (especially long-chain branch), advantageously reduces the melt viscosity of polymer in polymers；The cyclic acid anhydride is (such as
Maleic anhydride) use be conducive to improve PLA performance, while can also reduce the cost of polydactyl acid.Shown in Formulas I
Structure, the mol ratio for only showing alkene and unsaturated acid anhydride is 1:1, can be block copolymer, random copolymer, alternating copolymerization
Thing etc..In an instantiation, the copolymer is the alternate copolymer of alkene and unsaturated acid anhydride.
Polydactyl acid provided by the present invention, first by (multi-arm) star polyalcohols ester (such as star PBS) and described common
Polymers (shown in formula I) carries out melt blending with line style PLA, and reaction in-situ forms cross-linked structure, so as to improve PLA
Fragility.In above-mentioned polydactyl acid, the addition of the star polyalcohols ester (such as star PBS) can effectively reduce described modified poly-
The melt viscosity of lactic acid, while the copolymer (shown in formula I) of the hydroxyl of star polyalcohols ester (such as star PBS) and the composition c
Acid anhydrides there is esterification and crosslinking reaction, can improve the fragility of modified polylactic acid material, improve the toughness of modified polylactic acid material, carry
The elongation at break of the polydactyl acid high.By adjusting the content of each component, can obtain that toughness is controllable to be changed
Property PLA.
According to another aspect of the present invention, there is provided a kind of method for preparing above-mentioned polydactyl acid, it is including following
Step：
I. binary acid, dihydroxylic alcohols are polymerized in the presence of catalyst, are subsequently adding polyalcohol and proceed polymerization,
Obtain star polyalcohols ester；
Ii. alkene and unsaturated acid anhydride be polymerized obtaining copolymer,
Iii. the copolymer and linear polylactic acid that the star polyalcohols ester that will be obtained in step i, step ii are obtained enter
Row melt blending.
In a specific embodiment of the above method, the binary acid is selected from succinic acid and adipic acid；The dihydroxylic alcohols
Selected from ethylene glycol, butanediol and hexylene glycol.Wherein, binary acid and dihydroxylic alcohols are equimolar ratio, or binary acid is slightly excessive.It is described
Binary acid and the specifically used amount of dihydroxylic alcohols, can be determined by those skilled in the art by conventional method.
According to the present invention, the arm number of the star polyalcohols ester can be adjusted by choosing the polyalcohol of different hydroxy numbers
Control.The polyalcohol is the alcohols containing at least three hydroxyls.In another specific embodiment of the above method, the polyalcohol
Selected from glycerine, erythritol, xylitol, sorbic alcohol, pentaerythrite and bipentaerythrite.It is excellent in a preferred example
The addition of the polyalcohol is selected to account for 0.1~7mol% of binary acid, dihydroxylic alcohols and polyalcohol total amount.
According to a specific embodiment of the invention, in step i, succinic acid, BDO are pressed into certain mol proportion example
It is added in the reaction vessel for being connected with inert gas, is subsequently added catalyst, being to slowly warm up to reactant by oil bath melts, and rises
180~210 DEG C of high-temperature is dehydrated (the mainly generation of dimer).When dehydrating amount about theoretical calculation is worth 95%, heat up
To 300~230 DEG C and depressurize, carry out polymerisation 0.5~3 hour.Then polyalcohol is added to continue to react 0.5~3 hour,
Obtain multi-arm star PBS.
In another specific embodiment of the above method, the catalyst be selected from butyl titanate, tetraisopropyl titanate,
At least one in titanium dioxide and antimony oxide.In a specific embodiment, the addition of the catalyst accounts for two
0.05~0.5wt% of first acid, dihydroxylic alcohols and polyalcohol gross mass.
In another specific embodiment of the above method, the unsaturated acid anhydride is maleic anhydride.The alkene be containing
The 3-32 alkene of carbon atom, preferably containing 8 to 22 alkene of carbon atom.In a specific embodiment, the alkene
Preferably 1- octadecylenes.According to the present invention, the alkene obtains copolymer (copolymer shown in formula I) with unsaturated acid anhydride copolymerization
Reaction, be well known in the prior art, here is omitted.In a specific example, the unsaturated acid anhydride and alkene
The mol ratio of hydrocarbon is 1:1；The copolymer can be alternate copolymer.
According to another specific embodiment of method of the present invention, the temperature of the melt blending is 150~300
DEG C, preferably 180~190 DEG C；The time of the melt blending is 3~10min, preferably 5~8min.
According to another specific embodiment of method of the present invention, the melt blending is preferably in screw rod banbury
Carry out.The screw speed of the screw rod banbury is 50~130 revs/min, preferably 90~100 revs/min.
The modified effect of above-mentioned melt blending temperature, three factors of time and screw speed, suitable condition
Modified effect can be significantly improved.
Polydactyl acid provided by the present invention and linear macromolecule matrix phase ratio, its toughness are significantly improved, and
And can be by adjusting branched structure and multi-arm star polyalcohols ester (star PBS) and the institute of multi-arm star polyalcohols ester (star PBS)
The content of the copolymer (copolymer shown in formula I) of c is stated, the polydactyl acid of various different toughness can be obtained.Due to multi-arm
Star polyalcohols ester (star PBS) and the reaction of the copolymer (copolymer shown in formula I) of the c, can in the material form net
Shape structure, avoids the precipitation of low-molecular-weight admixture while improving product mechanical performance.To polydactyl acid system of the present invention
Into tensile bars carry out performance test, it has elongation at break very high.
The polydactyl acid of the reaction in-situ generation cross-linked structure provided according to the present invention, Regular Star Polymers can effectively drop
The melt viscosity of low matrix PLA, while the copolymer of copolymer (copolymer shown in formula I) with the c of c described in star
(copolymer shown in formula I) occurs esterification and crosslinking reaction can improve the fragility of PLA.According to the modified poly- breast that the present invention is provided
Acid has combination property higher, such as tensile strength and preferable toughness higher, the application prospect with broadness.
Specific embodiment
With reference to specific embodiment, the present invention will be further described, but does not constitute any limitation of the invention.
Method of testing：
Molecular weight and its distribution：Waters600E type liquid phase gel permeation chromatography (GPC) instrument of Waters companies, mobile phase
It is THF, test temperature is 35 DEG C.Curve determination is corrected using polystyrene standard.
Mechanical characteristic is tested：Batten overall length 50mm, width 4mm, testing length 2mm.Rate of extension 5mm/min, test
30 DEG C of temperature.
Embodiment 1：
The succinic acid and BDO of 1mol are added in the reaction vessel for being connected with inert gas respectively, are subsequently added
Catalyst butyl titanate 0.1mol%, is to slowly warm up to reactant and melts by oil bath, rises 300 DEG C of high-temperature and is dehydrated.
When dehydrating amount about theoretical calculation is worth 95%, be warmed up to 230 DEG C and depressurized, react 0.5 hour, add glycerine
3mol% continues reaction and obtains multi-arm star PBS in 0.5 hour, and number-average molecular weight 8600, molecular weight distribution 1.83 are tested through GPC.
By three-arm star-shaped PBS, the 1- octadecylene and maleic acid of the linear polylactic acid of weight average molecular weight 140,000 and above-mentioned preparation
(1- octadecylenes and the equimolar copolymer of maleic anhydride, its number-average molecular weight control three arms to the copolymer of acid anhydride 7800) to mix
The adding proportion (mass ratio) 2% or 10% of star PBS, the mol ratio of the acid anhydrides in the hydroxyl and copolymer of three-arm star-shaped PBS
It is 1：2.By said mixture in screw rod banbury melt blending, melt blending temperature be 185 DEG C, the screw speed of banbury
It is 100rpm, the melt blending time is 5 minutes.Sample is carried out into mechanical stretching test, elongation at break is respectively 15.3% He
40.6%.Data are shown in Table 1.
Embodiment 2：
The succinic acid and BDO of 1mol are added in the reaction vessel for being connected with inert gas respectively, are subsequently added
Catalyst butyl titanate 0.1mol%, is to slowly warm up to reactant and melts by oil bath, rises 300 DEG C of high-temperature and is dehydrated.
When dehydrating amount about theoretical calculation is worth 95%, be warmed up to 230 DEG C and depressurized, react 1 hour, add glycerine
3mol% continues reaction and obtains multi-arm star PBS in 1 hour, and number-average molecular weight 14000, molecular weight distribution 1.91 are tested through GPC.
The above-mentioned multi-arm star PBS for preparing is prepared into polydactyl acid by following steps.Preparation process is with implementation
Example 1, difference is the anhydride molar ratio 1 of the hydroxyl with copolymer of prepared multi-arm star PBS：1.Sample is carried out into machine
Tool extension test, elongation at break is respectively 17.5% and 61.6%.Data are shown in Table 1.
Embodiment 3：
The succinic acid and BDO of 1mol are added in the reaction vessel for being connected with inert gas respectively, are subsequently added
Catalyst butyl titanate 0.1mol%, is to slowly warm up to reactant and melts by oil bath, rises 300 DEG C of high-temperature and is dehydrated.
When dehydrating amount about theoretical calculation is worth 95%, be warmed up to 230 DEG C and depressurized, react 2 hours, add glycerine
3mol% continues reaction and obtains multi-arm star PBS in 1.5 hours, and number-average molecular weight 27000, molecular weight distribution 1.98 are tested through GPC.
The above-mentioned multi-arm star PBS for preparing is prepared into polydactyl acid by following steps.Preparation process is with implementation
Example 1, difference is the hydroxyl and anhydride molar ratio 1 of prepared multi-arm star PBS：1.Sample is carried out into mechanical stretching survey
Examination, elongation at break is respectively 11.7% and 32.6%.Data are shown in Table 1.
Embodiment 4：
With embodiment 1, difference is to add 2mol% grams of pentaerythrite, four for obtaining for the preparation of four arm star PBS
The number-average molecular weight 10700 of arm star PBS, molecular weight distribution 1.89.
The above-mentioned four arm star PBS for preparing are prepared into polydactyl acid by following steps.Preparation process is with implementation
Example 1.Sample is carried out into mechanical stretching test, elongation at break is respectively 18.5% and 47.3%.
Data are shown in Table 1.
Embodiment 5 (contrast)
The preparation of multi-arm star PBS with embodiment 1, the number-average molecular weight of the multi-arm star PBS obtained through gpc measurement
8600, molecular weight distribution 1.83.
By the linear polylactic acid of weight average molecular weight 140,000 and the multi-arm star PBS of above-mentioned preparation, control multi-arm star PBS's
Adding proportion (mass ratio) 10%.By said mixture in screw rod banbury melt blending, melt blending temperature be 185 DEG C,
The screw speed of banbury is 100rpm, and the melt blending time is 5 minutes.Sample is carried out into mechanical stretching test, extension at break
Rate is 8.6%.Data are shown in Table 1.
Comparative example 1
The linear polylactic acid of weight average molecular weight 140,000 is melted in screw rod banbury, melt temperature is 185 DEG C, banbury
Screw speed be 100rpm, the melting time be 5 minutes.Sample is carried out into mechanical stretching test, elongation at break is 5.6%.
Data are shown in Table 1.
The measuring mechanical property result of table 1
From table 1 it follows that there is mechanical performance higher according to the polydactyl acid obtained by the present invention, ensureing
While material has tensile strength higher, the toughness of material can be greatly improved, such as elongation at break, overcome conventional increasing
Modeling, the deficiency of flexibilizer additive polydactyl acid combination property.Additionally, by adjust the branched arm number of PBS, star PBS's plus
Enter the ratio of amount and multi-arm star PBS and copolymer, it is also possible to effectively adjust the toughness of the modified polylactic acid material.
It should be noted that embodiment described above is only used for explaining the present invention, do not constitute to of the invention any
Limitation.By referring to exemplary embodiments, invention has been described, it should be appreciated that word wherein used is descriptive
With explanatory vocabulary, rather than limited vocabulary.The present invention can be made within the scope of the claims by regulation
Modification, and the present invention is revised in without departing substantially from scope and spirit of the present invention.Although the present invention described in it is related to
And specific method, material and embodiment, it is not intended that the present invention is limited to wherein disclosed particular case, conversely, this hair
It is bright to can be extended to other all methods and applications with identical function.
Claims (17)
1. a kind of polydactyl acid, it is the melt blended material comprising following components：
Component a. star polyalcohols esters, the number-average molecular weight of the star polyalcohols ester is 500~30000, and the component a is selected from star
Polyethylene glycol succinate, star poly butylene succinate, star poly-succinic hexylene glycol ester, star polyadipate ethylene glycol
At least one in ester, star poly adipate succinic acid ester and star polyadipate hexylene glycol ester；
Component b. linear polylactic acids, the weight average molecular weight of the linear polylactic acid is 10~400,000；With
The copolymer of component c. alkene and unsaturated acid anhydride.
2. polydactyl acid according to claim 1, it is characterised in that the amount of the component a stars polyalcohols ester accounts for modified
2~30wt% of PLA total amount.
3. polydactyl acid according to claim 2, it is characterised in that the amount of the component a stars polyalcohols ester accounts for modified
2~10wt% of PLA total amount.
4. polydactyl acid according to claim 1, it is characterised in that the acid in hydroxyl in the component a and component c
The mol ratio of acid anhydride is 1:(1~8).
5. the polydactyl acid according to any one in claim 1-4, it is characterised in that described common in the component c
The structural formula of polymers is
In formula, R is containing the 1-30 alkyl of carbon atom, 1≤n≤100.
6. polydactyl acid according to claim 5, it is characterised in that R is the alkyl containing 6-20 carbon atoms.
7. a kind of method for preparing polydactyl acid described in any one in Claims 1 to 4, comprises the following steps：
I. binary acid, dihydroxylic alcohols are polymerized in the presence of catalyst, are subsequently adding polyalcohol and proceed polymerization, obtained
Star polyalcohols ester；
Ii. alkene and unsaturated acid anhydride be polymerized obtaining copolymer,
Iii. the copolymer and linear polylactic acid that the star polyalcohols ester that will be obtained in step i, step ii are obtained are melted
Melt blending；
Wherein, the binary acid is selected from succinic acid and adipic acid；The dihydroxylic alcohols is selected from ethylene glycol, butanediol and hexylene glycol.
8. method according to claim 7, it is characterised in that the polyalcohol is selected from glycerine, erythritol, xylose
Alcohol, sorbic alcohol, pentaerythrite and bipentaerythrite.
9. method according to claim 8, it is characterised in that the addition of the polyalcohol account for binary acid, dihydroxylic alcohols and
0.1~7mol% of polyalcohol total amount.
10. method according to claim 7, it is characterised in that the catalyst is selected from butyl titanate, the isopropyl of metatitanic acid four
At least one in ester, titanium dioxide and antimony oxide.
11. methods according to claim 10, it is characterised in that the addition of the catalyst accounts for binary acid, dihydroxylic alcohols
With 0.05~0.5wt% of polyalcohol gross mass.
12. methods according to any one of claims of claim 7-10, it is characterised in that the unsaturated acid anhydride is maleic acid
Acid anhydride；The alkene is containing the 3-32 alkene of carbon atom.
13. methods according to any one of claims of claim 7-10, it is characterised in that the alkene is containing 8 to 22 carbon
The alkene of atom.
14. methods according to any one of claims of claim 7-10, it is characterised in that the temperature of the melt blending is
150~300 DEG C；The time of the melt blending is 3~10min.
15. methods according to any one of claims of claim 7-10, it is characterised in that the temperature of the melt blending is
180~190 DEG C；The time of the melt blending is 5~8min.
16. method according to any one in claim 7~10, it is characterised in that the melt blending is close in screw rod
Carried out in mill, the screw speed of the screw rod banbury is 50~130 revs/min.
17. methods according to claim 16, it is characterised in that the screw speed of the screw rod banbury is 90~100
Rev/min.
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| US8058470B2 (en) * | 2006-09-04 | 2011-11-15 | Bio-Energy Corporation | Polyester polyol |
| TWI529212B (en) * | 2010-08-18 | 2016-04-11 | Vertellus Specialties Inc | Compositions, methods and articles produced by compounding polymides with olefin-maleic anhydride polymers |
| CN102286143B (en) * | 2011-06-22 | 2013-03-13 | 同济大学 | Preparation method of thermosetting polylactic acid |
| CN104086960B (en) * | 2013-04-01 | 2016-04-27 | 中国石油化工股份有限公司 | A kind of polylactic acid composition and preparation method thereof |
| CN103626982B (en) * | 2013-11-04 | 2016-02-10 | 上海富元塑胶科技有限公司 | A kind of method improving the melt strength of polyester resin |
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