CN106317816A - Low-cost toughening polylactic-acid composite material and preparation method thereof - Google Patents
Low-cost toughening polylactic-acid composite material and preparation method thereof Download PDFInfo
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- CN106317816A CN106317816A CN201610810392.7A CN201610810392A CN106317816A CN 106317816 A CN106317816 A CN 106317816A CN 201610810392 A CN201610810392 A CN 201610810392A CN 106317816 A CN106317816 A CN 106317816A
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- polylactic acid
- epoxy
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- vegetable oil
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- 239000004626 polylactic acid Substances 0.000 title claims abstract description 62
- 229920000747 poly(lactic acid) Polymers 0.000 title claims abstract description 61
- 239000002131 composite material Substances 0.000 title claims abstract description 42
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 239000004593 Epoxy Substances 0.000 claims abstract description 31
- 239000011256 inorganic filler Substances 0.000 claims abstract description 21
- 229910003475 inorganic filler Inorganic materials 0.000 claims abstract description 21
- 235000015112 vegetable and seed oil Nutrition 0.000 claims abstract description 21
- 239000008158 vegetable oil Substances 0.000 claims abstract description 21
- 238000002156 mixing Methods 0.000 claims abstract description 15
- 239000003999 initiator Substances 0.000 claims abstract description 13
- 150000002978 peroxides Chemical class 0.000 claims abstract description 11
- 238000000034 method Methods 0.000 claims description 25
- 238000003756 stirring Methods 0.000 claims description 21
- 239000002994 raw material Substances 0.000 claims description 18
- 230000008569 process Effects 0.000 claims description 17
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 10
- FPAFDBFIGPHWGO-UHFFFAOYSA-N dioxosilane;oxomagnesium;hydrate Chemical compound O.[Mg]=O.[Mg]=O.[Mg]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O FPAFDBFIGPHWGO-UHFFFAOYSA-N 0.000 claims description 9
- 239000004342 Benzoyl peroxide Substances 0.000 claims description 8
- 235000019400 benzoyl peroxide Nutrition 0.000 claims description 8
- 239000003549 soybean oil Substances 0.000 claims description 8
- 235000012424 soybean oil Nutrition 0.000 claims description 8
- OMPJBNCRMGITSC-UHFFFAOYSA-N Benzoylperoxide Chemical compound C=1C=CC=CC=1C(=O)OOC(=O)C1=CC=CC=C1 OMPJBNCRMGITSC-UHFFFAOYSA-N 0.000 claims description 7
- -1 epoxyoleic acid methyl ester Chemical class 0.000 claims description 7
- 239000003921 oil Substances 0.000 claims description 7
- 235000019198 oils Nutrition 0.000 claims description 7
- 238000005453 pelletization Methods 0.000 claims description 7
- 235000019482 Palm oil Nutrition 0.000 claims description 6
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 claims description 6
- 239000002540 palm oil Substances 0.000 claims description 6
- 239000002253 acid Substances 0.000 claims description 5
- GJBRNHKUVLOCEB-UHFFFAOYSA-N tert-butyl benzenecarboperoxoate Chemical compound CC(C)(C)OOC(=O)C1=CC=CC=C1 GJBRNHKUVLOCEB-UHFFFAOYSA-N 0.000 claims description 5
- 239000004408 titanium dioxide Substances 0.000 claims description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 4
- 241001597008 Nomeidae Species 0.000 claims description 3
- 239000003240 coconut oil Substances 0.000 claims description 3
- 235000019864 coconut oil Nutrition 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 3
- CIHOLLKRGTVIJN-UHFFFAOYSA-N tert‐butyl hydroperoxide Chemical compound CC(C)(C)OO CIHOLLKRGTVIJN-UHFFFAOYSA-N 0.000 claims description 3
- AOJJSUZBOXZQNB-VTZDEGQISA-N 4'-epidoxorubicin Chemical compound O([C@H]1C[C@@](O)(CC=2C(O)=C3C(=O)C=4C=CC=C(C=4C(=O)C3=C(O)C=21)OC)C(=O)CO)[C@H]1C[C@H](N)[C@@H](O)[C@H](C)O1 AOJJSUZBOXZQNB-VTZDEGQISA-N 0.000 claims description 2
- 239000000945 filler Substances 0.000 claims description 2
- 235000012239 silicon dioxide Nutrition 0.000 claims description 2
- 239000000377 silicon dioxide Substances 0.000 claims description 2
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims 3
- 125000001931 aliphatic group Chemical group 0.000 claims 2
- 238000001125 extrusion Methods 0.000 claims 2
- 150000004702 methyl esters Chemical class 0.000 claims 2
- ZFFMLCVRJBZUDZ-UHFFFAOYSA-N 2,3-dimethylbutane Chemical group CC(C)C(C)C ZFFMLCVRJBZUDZ-UHFFFAOYSA-N 0.000 claims 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims 1
- 235000010469 Glycine max Nutrition 0.000 claims 1
- 244000068988 Glycine max Species 0.000 claims 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims 1
- 229910052791 calcium Inorganic materials 0.000 claims 1
- 239000011575 calcium Substances 0.000 claims 1
- 229910052799 carbon Inorganic materials 0.000 claims 1
- 238000006735 epoxidation reaction Methods 0.000 claims 1
- 229910052760 oxygen Inorganic materials 0.000 claims 1
- 239000001301 oxygen Substances 0.000 claims 1
- 239000000843 powder Substances 0.000 abstract description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 235000013305 food Nutrition 0.000 abstract description 4
- 229920000229 biodegradable polyester Polymers 0.000 abstract description 3
- 239000004622 biodegradable polyester Substances 0.000 abstract description 3
- 231100000252 nontoxic Toxicity 0.000 abstract description 3
- 230000003000 nontoxic effect Effects 0.000 abstract description 3
- 239000012745 toughening agent Substances 0.000 abstract description 3
- 230000004048 modification Effects 0.000 abstract description 2
- 238000012986 modification Methods 0.000 abstract description 2
- 239000005022 packaging material Substances 0.000 abstract description 2
- 238000009826 distribution Methods 0.000 abstract 1
- 238000001035 drying Methods 0.000 abstract 1
- 238000011065 in-situ storage Methods 0.000 abstract 1
- 238000002844 melting Methods 0.000 abstract 1
- 230000008018 melting Effects 0.000 abstract 1
- 238000004381 surface treatment Methods 0.000 abstract 1
- 239000000463 material Substances 0.000 description 9
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 8
- 239000010954 inorganic particle Substances 0.000 description 7
- 229920003023 plastic Polymers 0.000 description 6
- 239000004033 plastic Substances 0.000 description 6
- XMNIXWIUMCBBBL-UHFFFAOYSA-N 2-(2-phenylpropan-2-ylperoxy)propan-2-ylbenzene Chemical compound C=1C=CC=CC=1C(C)(C)OOC(C)(C)C1=CC=CC=C1 XMNIXWIUMCBBBL-UHFFFAOYSA-N 0.000 description 5
- 150000002924 oxiranes Chemical class 0.000 description 5
- 229910000019 calcium carbonate Inorganic materials 0.000 description 4
- 238000004132 cross linking Methods 0.000 description 4
- 238000011161 development Methods 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000000470 constituent Substances 0.000 description 3
- 239000002114 nanocomposite Substances 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 241000196324 Embryophyta Species 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000003431 cross linking reagent Substances 0.000 description 2
- RWGFKTVRMDUZSP-UHFFFAOYSA-N cumene Chemical compound CC(C)C1=CC=CC=C1 RWGFKTVRMDUZSP-UHFFFAOYSA-N 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical compound CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- ODLMAHJVESYWTB-UHFFFAOYSA-N propylbenzene Chemical compound CCCC1=CC=CC=C1 ODLMAHJVESYWTB-UHFFFAOYSA-N 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 210000000582 semen Anatomy 0.000 description 2
- 230000004913 activation Effects 0.000 description 1
- 150000001263 acyl chlorides Chemical class 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000006065 biodegradation reaction Methods 0.000 description 1
- 239000003519 biomedical and dental material Substances 0.000 description 1
- 230000002153 concerted effect Effects 0.000 description 1
- AIMMVWOEOZMVMS-UHFFFAOYSA-N cyclopropanecarboxamide Chemical compound NC(=O)C1CC1 AIMMVWOEOZMVMS-UHFFFAOYSA-N 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 230000005713 exacerbation Effects 0.000 description 1
- 150000002333 glycines Chemical class 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000012948 isocyanate Substances 0.000 description 1
- 150000002513 isocyanates Chemical class 0.000 description 1
- 235000014655 lactic acid Nutrition 0.000 description 1
- 239000004310 lactic acid Substances 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 229920001896 polybutyrate Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 235000020238 sunflower seed Nutrition 0.000 description 1
- 229920002725 thermoplastic elastomer Polymers 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
- C08L67/04—Polyesters derived from hydroxycarboxylic acids, e.g. lactones
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/92—Measuring, controlling or regulating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92504—Controlled parameter
- B29C2948/9258—Velocity
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92504—Controlled parameter
- B29C2948/92704—Temperature
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/06—Biodegradable
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Biological Depolymerization Polymers (AREA)
Abstract
The invention discloses a low-cost toughening polylactic-acid composite material and a preparation method thereof. The low-cost toughening polylactic-acid composite material is composed of, by weight, 54.3-81.9wt% of polylactic acid, 8-15wt% of epoxidized vegetable oil, 10-30wt% of inorganic filler without surface treatment and peroxide initiator and is prepared by being melt, blended, modified and extruded through a twin-screw extruder in one step via drying and mixing, wherein weight-average molecular weight of the polylactic acid is 100-180 thousand, distribution index of the molecular weight is 1.2-2.0, and epoxy value of the epoxidized vegetable oil is 4.5-7. During melting and blending, the inorganic filler is subjected to surface modification of in-situ grafted stems, difficulty in pretreatment of the surface of traditional powder is avoided, the composite material good in mechanical property can also be prepared without adopting of other expensive biodegradable polyester as toughening agents, and production cost is greatly lowered; the composite materials is non-toxic, capable of completely degraded and suitable for making disposable dishware, food and medical packaging materials.
Description
Technical field
The present invention relates to a kind of low cost, modified technique simple plasticizing polylactic acid based composites and preparation method thereof,
Particularly relate to polylactic resin of a kind of inorganic particle addition height, excellent in mechanical performance and preparation method thereof.
Background technology
Along with the notable growth of economic development, plastic demand and consumption, plastics industry is made to produce fast development.Plastics
While consumption increases rapidly, garbage public hazards also become global concern focal issue.A large amount of generations of waste plastic not only increase
Having added the financial burden in terms of cost of disposal, and caused environmental pollution, additionally China's oil base plastics industry also faces
The predicament of shortage of raw materials, one of effective way solving these problems, it is simply that exploitation Biodegradable material.
Polylactic acid (PLA) is a kind of biodegradation material deriving from the Renewable resource such as Semen Maydis, Semen Tritici aestivi, intensity and rigidity
Excellence, in the later stage nineties, has begun to heavy industrialization.At present, the biggest in the world polylactic acid manufacturer U.S.
Natureworks company, 2009 annual capacities just reach 150,000 tons/year；In recent years, China also builds up many ton PLA productions
Line.Active development popularization and application polylactic acid article, to China market consumption and automobile, packaging, food, environmental protection cause development all
To have particularly important meaning.Polylactic acid article produces and the focus of exploitation always countries in the world research.But owing to PLA becomes
This height, price is several times of resins for universal use (such as polyolefin, polyesters), and itself enbrittle greatly, impact resistance difference etc. shortcoming,
Limit the promotion and application of polylactic acid article.
Inorganic filler is industrial conventional polymer composites additive, can reduce goods cost, strengthen polymerization
Thing, raising heat stability and dimensional stability etc., but the interface binding power between inorganic filler and polymeric matrix is to whole compound
The performance of material plays vital effect.For the research of inorganic powder filled polylactic acid, existing many reports, China is specially
Profit CN101333331A, CN103965596B and CN100537661C disclose inorganic powder filled polylactic acid-base composite material
Preparation method, the addition of inorganic particle may be up to 30 ~ 40wt%, and heat-resist, but inorganic particle is required to carry out surface
Processing activation, wherein wet processing process is relatively complicated, time-consuming, and production efficiency is low is unfavorable for industrialization promotion.
In polylactic acid modified preparation method for material disclosed in CN101955639A, although avoid the pretreating process of inorganic filler, but select
By Polyurethane Thermoplastic Elastomer as toughener, have impact on the biological degradability of composite, make the material can not be degradable.
In fully-degradable polylactic acid based composites prepared by CN103113727A, CN101362853A and CN104072957B, although nothing
The addition of machine powder body is the highest, but its component is selected low molecular weight or Biodegradable polyester (as PBS, PBAT,
PHA etc.) carry out toughening modifying, relatively costly.Also have been reported that by using bis-oxazoline, acyl chlorides, isocyanates etc. as crosslinking
Agent, improves lactic acid composite material toughness, but these cross-linking agent toxicity is relatively big, even if minimal residue also limit polylactic acid article
In field application such as medical treatment, food.The present invention develops the plasticizing polylactic acid based composites of a kind of low cost full-biodegradable,
This preparation method causes between component generation situ-formed graft cross-linking reaction during melt blending, and all components is the most nontoxic, can give birth to
Thing is degraded, and technique is simple, cheap, be prone to industrialized production.
Summary of the invention
It is an object of the present invention to provide a kind of low cost plasticizing polylactic acid based composites and preparation method thereof, its technological process
Simply, easily-controllable, composite is with low cost, biodegradable, can be used for disposable tableware, food and medical packaging material,
The fields such as bio-medical material.
The present invention provide a kind of low cost plasticizing polylactic acid based composites, by 54.3 ~ 81.9 wt% polylactic acid, 8 ~
Inorganic filler that 15wt % epoxidized vegetable oil or derivatives thereof, 10 ~ 30wt% process without surface, 0.1 ~ 0.7wt % peroxide
Compound initiator four component, after being dried, mixing, extruding pelletization system modified by double screw extruder one step melt blending
?.
Wherein, the weight average molecular weight of described polylactic acid be 10 ~ 180,000, molecular weight distributing index be 1.2 ~ 2.0；Described without
Cross inorganic filler a size of 1250 ~ 8000 mesh that surface processes.
Described double screw extruder rotating speed is 120 ~ 300 rpm, and each section of temperature selects between 130 DEG C ~ 200 DEG C.
In preferred embodiment, above-mentioned nanocomposite constituents is by 59.3 ~ 79.8 wt% polylactic acid, 10 ~ 15wt % epoxy
Change inorganic filler, 0.2 ~ 0.7wt % peroxide initiator that vegetable oil or derivatives thereof, 10 ~ 25wt% process without surface
Composition；Described polylactic acid preferable weight-average molecular weight is 13 ~ 170,000, and molecular weight distributing index is 1.3 ~ 1.6.
In above-mentioned composite, described epoxidized vegetable oil is epoxy soybean oil, epoxy Semen Lini oil, epoxy sunflower seed
One or more in oil, epoxy palm oil, epoxy coconut oil；The derivant of described epoxidized vegetable oil is epoxyfatty acid first
At least one in ester, epoxyoleic acid methyl ester.The epoxide number of described epoxidized vegetable oil or derivatives thereof is 4.5 ~ 7.
The described inorganic filler processed without surface is in calcium carbonate, Pulvis Talci, silicon dioxide and titanium dioxide
Plant or two kinds.
Described peroxide initiator be cumyl peroxide, benzoyl peroxide, peroxidized t-butyl perbenzoate, 2,
5-dimethyl-2, one or both in 5-bis-(tert-butyl hydroperoxide) hexane, wherein, two kinds of compound proportions are 2:1 ~ 1:2.
The present invention also provides for the preparation method of a kind of low cost plasticizing polylactic acid based composites, and the method comprising the steps of:
S1. each raw material is dried at 60 ~ 100 DEG C 8 ~ 20h；By polylactic acid: epoxidized vegetable oil or derivatives thereof: without
The inorganic filler that surface processes: peroxide initiator=54.3 ~ 81.9:8 ~ 15:10 ~ 30:0.1 ~ 0.7 weight proportion claims
Take dried raw material；
S2. charging order by merging can select one of following two operation, first polylactic acid is placed in height and stirs in machine；By peroxidating
Thing initiator joins in epoxidized vegetable oil or derivatives thereof and stirs, and is then added dropwise to 700 ~ 900r/min low
In the polylactic acid of speed stirring, drip and finish with 700 ~ 900r/min mixed on low speed 5 ~ 10min, be eventually adding the nothing processed without surface
Machine filler also obtains pre-composition with 1300 ~ 1800r/min high-speed stirred；
Or, first the inorganic filler processed without surface is placed in height and stirs in machine, peroxide initiator is joined epoxy
Change in vegetable oil or derivatives thereof and stir, then be added dropwise to 700 ~ 900r/min stirring at low speed without surface
In the inorganic filler of reason, drip and finish with 1300 ~ 1800r/min mixed at high speed 5 ~ 10min, be eventually adding polylactic acid with 1300 ~
1800r/min high-speed stirred obtains pre-composition；
S3. described pre-composition is modified by double screw extruder one step melt blending, extruding pelletization, obtain composite；.
In this preparation method, each section of temperature of double screw extruder is set as: heats 130 DEG C ~ 145 DEG C of a district, heat 2nd district
140 DEG C ~ 170 DEG C, heat 160 ~ 200 DEG C of 3rd district, heat 170 DEG C ~ 200 DEG C of 4th district, heat 180 DEG C ~ 200 DEG C of 5th district, heating six
170 DEG C ~ 200 DEG C of district, heating 170 DEG C ~ 200 DEG C of 7th district, head temperature 140 DEG C ~ 170 DEG C, double screw extruder rotating speed is 120 ~
300 rpm。
The method have the advantages that
Full-biodegradable polylactic acid based composites provided by the present invention, uses one-step method to carry out melt blending, and this technique exists
During preparing composite, inorganic filler is carried out situ-formed graft surface modification, it is to avoid traditional powder surface is located in advance
Science and engineering skill；Its epoxidized vegetable oil or derivatives thereof derives from natural plants, nontoxic, with low cost, it is to avoid use other prices
Expensive Biodegradable polyester is as toughener, so that the production cost of full-biodegradable polylactic acid based articles is greatly reduced,
And between nanocomposite constituents, there is graft crosslinking reaction, the surface migration of epoxidized vegetable oil or derivatives thereof can be suppressed to analyse
Go out, make plasticizing polylactic acid goods keep the mechanical property of excellence for a long time.
Owing to there is situ-formed graft cross-linking reaction during melt blending between component, therefore charging sequence is to composite
Can affect notable；Use the inventive method to be not only greatly improved powder body and basal body interface adhesion, make inorganic particle addition
It is significantly increased, still can prepare the polylactic acid-base composite material of excellent in mechanical performance.
Graft crosslinking structure between nanocomposite constituents of the present invention can dramatically increase the interface knot between inorganic filler and matrix
Make a concerted effort, make composite materials property be greatly improved, while especially toughness is greatly improved, also maintain higher strong
Degree, when inorganic particle addition is up to 25wt%, composite materials property does not all have severe exacerbation；In optimization formula, epoxy is big
When Oleum Glycines addition is 10 wt%, inorganic particle addition is up to 20wt%, only with the peroxide initiator of 0.5wt%, so that it may
Making fracture of composite materials percentage elongation improve to 266%, maintain hot strength is 33MPa simultaneously；Inorganic particle addition is 15wt%
Time, plasticizing polylactic acid based composites can be prepared, its elongation at break is 366%, and hot strength reaches 32MPa.Of the present invention
Low cost plasticizing polylactic acid based composites is a kind of resins for universal use, available plastic uptake, be blow molded, the technique such as injection is shaped adding
Work.
Detailed description of the invention
In order to further appreciate that the present invention, below in conjunction with embodiment, the preferred embodiments of the invention are described, but
Should be appreciated that these describe simply as further illustrating the features and advantages of the present invention rather than to patent requirements of the present invention
Limiting, the present invention is not limited only to the content of these embodiments.Those skilled in the art are according to present inventive concept, these descriptions also
Any improvement of making in conjunction with general knowledge known in this field, equivalents, should be included in the protection of the claims in the present invention
In the range of.
Embodiment 1: dispensing: weight average molecular weight be 170,000 molecular weight distributing index be 1.3 polylactic acid, epoxide number be 6.6
Epoxy soybean oil, 5000 mesh Pulvis Talci (without surface process) and peroxidized t-butyl perbenzoate be raw material, the weight of raw material
Amount ratio is for polylactic acid: epoxy soybean oil: Pulvis Talci: peroxidized t-butyl perbenzoate=69.5:10:20:0.5.
Preparation method:
By above-mentioned raw materials after 60 DEG C of vacuum oven 8 hours, weigh dried raw material by proportioning, first Pulvis Talci is placed in
Height stirs in machine, is joined in epoxy soybean oil by peroxidized t-butyl perbenzoate and stirs, then is added dropwise to 900r/
In the Pulvis Talci of min stirring at low speed, drip and finish with 1800r/min mixed at high speed 10min, be eventually adding polylactic acid with 1800r/min
High-speed stirred obtains pre-composition；
Above-mentioned premix material is added double screw extruder melt blending modified, extruding pelletization；Double screw extruder draw ratio is 40,
Double screw extruder rotating speed is 264 rpm, and each section of temperature of double screw extruder is set as: heats 135 DEG C of a district, heat 2nd district
150 DEG C, heat 165 DEG C of 3rd district, heat 175 DEG C of 4th district, heat 180 DEG C of 5th district, heat 175 DEG C of 6th district, heat 170 DEG C of 7th district,
Head temperature 160 DEG C.
The low cost plasticizing polylactic acid based composites prepared, is tested by GB-T1040.1-2006, and elongation at break is
266%, hot strength is 33 MPa.
Embodiment 2: dispensing: weight average molecular weight be 130,000 molecular weight distributing index be 1.3 polylactic acid, epoxide number be 6.6
Epoxy soybean oil, 2000 mesh Pulvis Talci (without surface process) and benzoyl peroxide be raw material, the weight ratio of raw material is
Polylactic acid: epoxy soybean oil: Pulvis Talci: benzoyl peroxide=74.8:10:15:0.2.
Preparation method:
By above-mentioned raw materials after 65 DEG C of vacuum oven 10 hours, first polylactic acid is placed in height and stirs in machine, by benzoyl peroxide
Formyl joins in epoxy soybean oil and stirs, then is added dropwise in the polylactic acid with 800r/min stirring at low speed, drips and finishes
With 700r/min mixed on low speed 10min, it is eventually adding Pulvis Talci and obtains pre-composition with 1700r/min high-speed stirred；
Above-mentioned premix material is added double screw extruder melt blending modified, extruding pelletization, double screw extruder draw ratio is 40,
Double screw extruder rotating speed is 264 rpm, and each section of temperature of double screw extruder is set as: heats 135 DEG C of a district, heat 2nd district
150 DEG C, heat 160 DEG C of 3rd district, heat 170 DEG C of 4th district, heat 175 DEG C of 5th district, heat 175 DEG C of 6th district, heat 170 DEG C of 7th district,
Head temperature 155 DEG C.
The low cost plasticizing polylactic acid based composites prepared, is tested by GB-T1040.1-2006, and elongation at break is
366%, hot strength is 32 MPa.
Embodiment 3: dispensing: weight average molecular weight be 170,000 molecular weight distributing index be 1.3 polylactic acid, epoxide number be 5.5
Epoxy palm oil, 5000 mesh calcium carbonate (without surface process) and cumyl peroxide be raw material, the weight of raw material
Ratio is for polylactic acid: epoxy palm oil: calcium carbonate: cumyl peroxide=59.3:15:25:0.7.
Preparation method:
By above-mentioned raw materials after 70 DEG C of vacuum oven 8 hours, first polylactic acid is placed in height and stirs in machine, by different for peroxidating two
Propyl benzene joins in epoxy palm oil and stirs, then is added dropwise in the polylactic acid with 700r/min stirring at low speed, drips and finishes
With 700r/min mixed on low speed 6min, it is eventually adding calcium carbonate and obtains pre-composition with 1500r/min high-speed stirred；
Above-mentioned premix material is added double screw extruder melt blending modified, extruding pelletization；Double screw extruder draw ratio is 40,
Double screw extruder rotating speed is 150 rpm, and each section of temperature of double screw extruder is set as: heats 145 DEG C of a district, heat 2nd district
155 DEG C, heat 170 DEG C of 3rd district, heat 180 DEG C of 4th district, heat 180 DEG C of 5th district, heat 185 DEG C of 6th district, heat 185 DEG C of 7th district,
Head temperature 160 DEG C.
The low cost plasticizing polylactic acid based composites prepared, is tested by GB-T1040.1-2006, and elongation at break is
50%, hot strength is 38MPa.
Embodiment 4: dispensing: weight average molecular weight be 160,000 molecular weight distributing index be 1.4 polylactic acid, epoxide number be 4.0
Epoxyoleic acid methyl ester, 1250 mesh titanium dioxide (without surface process) and cumyl peroxide, benzoyl peroxide be
Raw material, the weight ratio of raw material is polylactic acid: epoxyoleic acid methyl ester: titanium dioxide: cumyl peroxide: benzoyl peroxide=
74.7:10:15:0.1:0.2。
Preparation method:
By above-mentioned raw materials after 65 DEG C of vacuum oven 12 hours, first polylactic acid is placed in height and stirs in machine, by peroxidating two
Isopropylbenzene and benzoyl peroxide join in epoxyoleic acid methyl ester and stir, then are added dropwise to stir with 800r/min low speed
In the polylactic acid mixed, drip and finish with 800r/min mixed on low speed 8min, be eventually adding titanium dioxide and obtain with 1600r/min high-speed stirred
Pre-composition；
Above-mentioned premix material is added double screw extruder melt blending modified, extruding pelletization；Double screw extruder draw ratio is 40,
Double screw extruder rotating speed is 280 rpm, and each section of temperature of double screw extruder is set as: heats 135 DEG C of a district, heat 2nd district
145 DEG C, heat 165 DEG C of 3rd district, heat 170 DEG C of 4th district, heat 175 DEG C of 5th district, heat 175 DEG C of 6th district, heat 180 DEG C of 7th district,
Head temperature 155 DEG C.
The low cost plasticizing polylactic acid based composites prepared, is tested by GB-T1040.1-2006, and elongation at break is
243%, hot strength is 30MPa.
Claims (10)
1. a low cost plasticizing polylactic acid based composites, it is characterised in that this composite is by the poly-breast of 54.3 ~ 81.9 wt%
Inorganic filler that acid, 8 ~ 15wt % epoxidized vegetable oil or derivatives thereof, 10 ~ 30wt% process without surface, 0.1 ~ 0.7wt
% peroxide initiator four component, after being dried, mixing, extrusion modified by double screw extruder one step melt blending is made
Grain prepares；
Wherein, the weight average molecular weight of described polylactic acid be 10 ~ 180,000, molecular weight distributing index be 1.2 ~ 2.0；Described without table
Inorganic filler a size of 1250 ~ 8000 mesh that face processes.
Composite the most according to claim 1, it is characterised in that described composite is by the poly-breast of 59.3 ~ 79.8 wt%
Inorganic filler that acid, 10 ~ 15wt % epoxidized vegetable oil or derivatives thereof, 10 ~ 25wt% process without surface, 0.2 ~ 0.7wt
% peroxide initiator forms；Wherein, the weight average molecular weight of described polylactic acid is 13 ~ 170,000, molecular weight distributing index is 1.3 ~
1.6。
Composite the most according to claim 1 and 2, it is characterised in that described double screw extruder rotating speed is 120 ~ 300
Rpm, each section of temperature selects between 130 DEG C ~ 200 DEG C.
Composite the most according to claim 1, it is characterised in that described epoxidized vegetable oil is epoxy soybean oil, ring
One or more in oxygen Semen Lini oil, epoxy Oleum Helianthi, epoxy palm oil, epoxy coconut oil；Described epoxidized vegetable oil
Derivant be at least one in epoxy aliphatic acid methyl ester, epoxyoleic acid methyl ester.
Composite the most according to claim 1, it is characterised in that the epoxy of described epoxidized vegetable oil or derivatives thereof
Value is 4.5 ~ 7.
Composite the most according to claim 1, it is characterised in that the described inorganic filler processed without surface is carbon
One or both in acid calcium, Pulvis Talci, silicon dioxide and titanium dioxide.
Composite the most according to claim 1, it is characterised in that described peroxide initiator is peroxidating diisopropyl
In benzene, benzoyl peroxide, peroxidized t-butyl perbenzoate, 2,5-dimethyl-2,5-two (tert-butyl hydroperoxide) hexane one
Planting or two kinds, wherein, two kinds of compound proportions are 2:1 ~ 1:2.
8. the preparation method of a low cost plasticizing polylactic acid based composites, it is characterised in that comprise the steps:
S1. each raw material is dried at 60 ~ 100 DEG C 8 ~ 20h；By polylactic acid: epoxidized vegetable oil or derivatives thereof: without
The inorganic filler that surface processes: peroxide initiator=54.3 ~ 81.9:8 ~ 15:10 ~ 30:0.1 ~ 0.7 weight proportion claims
Take dried raw material；
The most first inorganic filler by polylactic acid or without surface process is placed in height and stirs in machine；Peroxide initiator is added
Enter and stir in epoxidized vegetable oil or derivatives thereof, be then added dropwise to stirring at low speed polylactic acid or without
In the inorganic filler that surface processes, drip and finish with low speed or mixed at high speed 5 ~ 10min, be eventually adding the nothing processed without surface
Machine filler or polylactic acid high-speed stirred obtain pre-composition；Wherein, described low-speed range is 700 ~ 900r/min, described high speed model
Enclosing is 1300 ~ 1800r/min；
S3. described pre-composition is modified by double screw extruder one step melt blending, extruding pelletization；Wherein, twin-screw extrusion
Each section of temperature of machine is set as: heats 130 DEG C ~ 145 DEG C of a district, heat 140 DEG C ~ 170 DEG C of 2nd district, heat 160 ~ 200 DEG C of 3rd district, add
170 DEG C ~ 200 DEG C of 4th district of heat, heat 180 DEG C ~ 200 DEG C of 5th district, heat 170 DEG C ~ 200 DEG C of 6th district, heat seven districts 170 DEG C ~ 200
DEG C, head temperature 140 DEG C ~ 170 DEG C, double screw extruder rotating speed is 120 ~ 300 rpm.
Preparation method the most according to claim 8, it is characterised in that the epoxy of described epoxidized vegetable oil or derivatives thereof
Value is 4.5 ~ 7.
Preparation method the most according to claim 8 or claim 9, it is characterised in that described epoxidized vegetable oil is epoxy soybean
One or more in oil, epoxy Semen Lini oil, epoxy Oleum Helianthi, epoxy palm oil, epoxy coconut oil；Described epoxidation is planted
The derivant of thing oil is at least one in epoxy aliphatic acid methyl ester, epoxyoleic acid methyl ester.
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Address after: Shenzhen Graduate School of Guangdong Province, Shenzhen City Xili 518055 Nanshan District University City Tsinghua University Patentee after: Tsinghua Shenzhen International Graduate School Address before: Shenzhen Graduate School of Guangdong Province, Shenzhen City Xili 518055 Nanshan District University City Tsinghua University Patentee before: GRADUATE SCHOOL AT SHENZHEN, TSINGHUA University |