Detailed Description
The following describes specific embodiments of the present invention in detail. It should be understood that the detailed description and specific examples, while indicating and illustrating the invention, are not intended to limit the invention.
According to a first aspect of the present invention there is provided a biodegradable material composition, the composition consisting of: PBST, talc, polyethylene glycol, optionally a chain extender and optionally an antioxidant;
Based on the total weight of PBST and talcum powder, the dosage of PBST is 85-99 wt%, and the dosage of talcum powder is 1-15 wt%; the dosage of polyethylene glycol is 2-15% of the total weight of PBST and talcum powder, the dosage of chain extender is 0-5% of the total weight of PBST and talcum powder, and the dosage of antioxidant is 0-1.5% of the total weight of PBST and talcum powder.
In the present invention, the PBST (polybutylene terephthalate-polybutylene succinate copolymer) is a copolymer containing a repeating unit represented by the formulas (I) and (II);
In formula (I), m 1=4,n1 = 2;
in the PBST, the content of the repeating unit shown in the formula (II) is 45-55 mol%.
According to the invention, the talc has a particle size of 325 to 8000 mesh, preferably 2000 to 8000 mesh.
In the invention, the molecular weight of the polyethylene glycol is 200-600g/mol.
Preferably, PBST is used in an amount of 90 to 99% by weight and talc is used in an amount of 1 to 10% by weight, based on the total weight of PBST and talc.
According to the present invention, the chain extender and the antioxidant may be of various types conventionally used in the art. For example, the antioxidant may be a hindered phenolic antioxidant, a phosphite antioxidant, a pentaerythritol ester antioxidant; the chain extender may be a difunctional acid derivative, isocyanate, anhydride, epoxide.
In the present invention, various raw materials may be prepared or commercially available, and the source thereof is not particularly limited as long as the above-mentioned parameter requirements are satisfied.
The PBST of the invention can be prepared by the following method, which comprises the following steps:
(1) Contacting and prepolymerizing diacid, ester thereof, anhydride thereof or mixture thereof, glycol and a first catalyst in a reaction kettle under vacuum condition to obtain prepolymer; the diacid refers to organic dicarboxylic acids such as terephthalic acid and succinic acid, and the diol refers to primary dibasic alcohols including butanediol;
(2) And (3) contacting a second catalyst with the prepolymer, and performing vacuum polycondensation reaction to obtain the PBST (polybutylene terephthalate-polybutylene succinate copolymer).
The invention has no special limitation on the mixing sequence of the components in the reaction system, and the dosage of the components is also based on the content of the structural units required by the product.
The reaction conditions of the individual steps according to the invention may also be those conventional in the art.
Specifically, in step (1), the reaction conditions of the prepolymerization may include: the reaction temperature is 190-250 ℃; the vacuum degree is 200-600Pa; the reaction time is 1-3 hours, or until the small molecules in the reaction system are nearly pumped down, the temperature of the fraction is kept unchanged.
In the step (2), the reaction conditions of the vacuum polycondensation reaction may include: the reaction temperature is 200-300 ℃; the vacuum degree is less than 300Pa; the reaction time is 3-12 hours.
The catalyst used in the polymerization reaction and the amount thereof are not particularly limited in the present invention, and various conventional catalysts for synthesizing polyesters and the amount of the conventional catalyst may be used. Wherein the catalysts used in step (1) and step (2) may be the same or different. For example, the catalyst used in step (1) may be selected from at least one of the compounds of the metals titanium, antimony and tin; the catalyst used in step (2) may be selected from the group consisting of compounds of rare earth metals Ln selected from at least one of lanthanoid elements, scandium, and yttrium, and mixtures thereof.
According to the invention, the step (1) and the step (2) can be carried out in the same reaction kettle or in different reaction kettles, namely, the prepolymer can be taken out to another reaction kettle to continue the subsequent polymerization reaction.
According to the present invention, nitrogen protection is generally used in the reaction system, but other atmospheres including air may be filled.
According to a second aspect of the present invention, there is provided a method of preparing the above biodegradable material composition, the method comprising: adding the raw materials into a high-speed stirrer for mixing to obtain a mixed material; and adding the mixed material into a double-screw extruder for melting, and extruding and granulating to obtain the biodegradable material composition.
In the present invention, the mixing time may be 1 to 10 minutes.
In a third aspect the present invention provides a biodegradable film article prepared from the composition described above.
According to the invention, the film product is processed by a blow molding method.
The blow molding method adopted by the invention can be conventionally set according to the prior art, and the following main settings and conditions are applicable:
1) The screw length may be 20 to 40 times the screw diameter.
2) Barrel and die temperatures may be in the range of 110-180 ℃.
3) The blow-up ratio may be 2 to 4.
4) The die diameter may be any commercial die size.
5) Film cooling may be performed with a cooling fluid, which may be liquid or gaseous. In the case of cooling with a liquid cooling medium, water is the preferred cooling medium and the extrusion direction may be vertically downward. In the case of cooling with a gaseous cooling medium, air is the preferred cooling medium, but other gases, such as nitrogen, may also be used, and the extrusion direction is preferably vertically upwards.
6) The cooling medium temperature may be 5 to 20 ℃.
7) Extrusion and blowing devices are film blowing devices known in the art.
The substances and parameters not defined in the present invention can be selected according to the prior art, and are conventional in the art.
The invention will be further illustrated with reference to the following examples. But are not limited by these examples.
In the following examples and comparative examples, the data were obtained as follows:
1. mechanical property testing, all mechanical properties were completed by an Instron 5965 universal tester.
2. The crystallization temperature of the material was determined by a TA company Q-100 DSC, the sample was isothermally heated at 200℃for 5 minutes to eliminate the heat history, and then cooled at 10℃per minute. The crystallization temperature was calculated as the peak temperature of the crystallization peak.
Examples 1-13 illustrate compositions of the present invention and methods of making the same.
Example 1
Polybutylene terephthalate-polybutylene succinate copolymer (PBST) and talcum powder are mixed according to the weight ratio of 99:1, and then 0.1 weight percent of chain extender, 5 weight percent of polyethylene glycol and 0.3 weight percent of antioxidant are added into the mixture. The weight percentages of the chain extender, the polyethylene glycol and the antioxidant are calculated according to the sum of the weight of PBST and the weight of talcum powder. Wherein, the polybutylene terephthalate-polybutylene succinate copolymer (PBST) is a pilot-scale product of Beijing chemical industry research institute, and the molar content of the repeating unit (II) is 50 percent. Talc powder is from Michelin Corp, 5000 mesh. The chain extender is BASF corporationADR 4468. Polyethylene glycol was obtained from Shanghai Ala Biochemical technologies Co., ltd and had a molecular weight of 600g/mol. The antioxidant is prepared by mixing BASF1010 and BASF168 according to a weight ratio of 1:1. Mixing the raw materials in a high-speed stirrer for 5min, melting the obtained mixture by a double-screw extruder, extruding and granulating to obtain the composition.
The resulting composition was processed into film articles by blow molding, and the specific production conditions and film properties are shown in Table 1.
Example 2
The procedure is as in example 1, except that polybutylene terephthalate-polybutylene succinate copolymer (PBST) and talc are compounded in a weight ratio of 95:5.
Example 3
The procedure is as in example 1, except that the polybutylene terephthalate-polybutylene succinate copolymer (PBST) and talc are formulated in a weight ratio of 90:10.
Example 4
The procedure is as in example 1, except that polybutylene terephthalate-polybutylene succinate copolymer (PBST) and talc are compounded in a weight ratio of 85:15.
Example 5
The difference is that the particle size of talc was changed to 8000 mesh as in example 1.
Example 6
The difference is that the particle size of talc was changed to 2000 mesh as in example 1.
Example 7
The difference was that the particle size of talc was changed to 325 mesh as in example 1.
Example 8
The same as in example 1 was conducted except that the weight fraction of polyethylene glycol was adjusted to 15%.
Example 9
The same as in example 1 was conducted except that the weight fraction of polyethylene glycol was adjusted to 2%.
Example 10
The same as in example 1, except that the polyethylene glycol molecular weight was changed to 200g/mol.
Example 11
The procedure is as in example 1, except that the polyethylene glycol molecular weight is changed to 400g/mol.
Example 12
The difference was that the molar content of the repeating unit (II) in the polybutylene terephthalate-polybutylene succinate copolymer (PBST) was 45% as in example 1.
Example 13
The difference was that the molar content of the repeating unit (II) in the polybutylene terephthalate-polybutylene succinate copolymer (PBST) was 55% as in example 1.
Comparative example 1
A polybutylene terephthalate-polybutylene succinate copolymer (PBST) material was taken, and 0.1 wt% of a chain extender and 0.3 wt% of an antioxidant were added to the material. The weight percentages of the chain extender and the antioxidant are calculated according to the weight of PBST. Wherein, the polybutylene terephthalate-polybutylene succinate copolymer (PBST) is a pilot-scale product of Beijing chemical industry research institute, and the molar content of the repeating unit (II) is 50 percent. The chain extender is BASF corporationADR 4468. The antioxidant is prepared by mixing BASF1010 and BASF168 according to a weight ratio of 1:1. Mixing the raw materials in a high-speed stirrer for 5min, melting the obtained mixture by a double-screw extruder, extruding and granulating to obtain the composition.
The resulting composition was processed into film articles by blow molding, and the specific production conditions and film properties are shown in Table 1.
Comparative example 2
A polybutylene terephthalate-polybutylene succinate copolymer (PBST) was taken, and 0.1% by weight of a chain extender, 5% by weight of polyethylene glycol, and 0.3% by weight of an antioxidant were added to the above-mentioned materials. The weight percentages of the chain extender, the polyethylene glycol and the antioxidant are calculated according to the weight of PBST. Wherein, the polybutylene terephthalate-polybutylene succinate copolymer (PBST) is a pilot-scale product of Beijing chemical industry research institute, and the molar content of the repeating unit (II) is 50 percent. The chain extender is BASF corporationADR 4468. Polyethylene glycol was obtained from Shanghai Ala Biochemical technologies Co., ltd and had a molecular weight of 600g/mol. The antioxidant is prepared by mixing BASF1010 and BASF168 according to a weight ratio of 1:1. Mixing the raw materials in a high-speed stirrer for 5min, melting the obtained mixture by a double-screw extruder, extruding and granulating to obtain the composition.
The resulting composition was processed into film articles by blow molding, and the specific production conditions and film properties are shown in Table 1.
Comparative example 3
Polybutylene terephthalate-polybutylene succinate copolymer (PBST) and talcum powder are mixed according to the weight ratio of 99:1, and then 0.1 weight percent of chain extender and 0.3 weight percent of antioxidant are added into the mixture. The weight percentages of the chain extender and the antioxidant are calculated according to the sum of the weight of PBST and the weight of talcum powder. Wherein, the polybutylene terephthalate-polybutylene succinate copolymer (PBST) is a pilot-scale product of Beijing chemical industry research institute, and the molar content of the repeating unit (II) is 50 percent. Talc powder is from Michelin Corp, 5000 mesh. The chain extender is BASF corporationADR4468. The antioxidant is prepared by mixing BASF1010 and BASF168 according to a weight ratio of 1:1. Mixing the raw materials in a high-speed stirrer for 5min, melting the obtained mixture by a double-screw extruder, extruding and granulating to obtain the composition.
The resulting composition was processed into film articles by blow molding, and the specific production conditions and film properties are shown in Table 1.
Comparative example 4
The polybutylene terephthalate-polybutylene succinate copolymer (PBST) and talcum powder are mixed according to the weight ratio of 80:20, and then 0.1 weight percent of chain extender, 5 weight percent of polyethylene glycol and 0.3 weight percent of antioxidant are added into the mixture. The weight percentages of the chain extender, the polyethylene glycol and the antioxidant are calculated according to the sum of the weight of PBST and the weight of talcum powder. Wherein, the polybutylene terephthalate-polybutylene succinate copolymer (PBST) is a pilot-scale product of Beijing chemical industry research institute, and the molar content of the repeating unit (II) is 50 percent. Talc powder is from Michelin Corp, 5000 mesh. The chain extender is BASF corporationADR 4468. Polyethylene glycol was obtained from Shanghai Ala Biochemical technologies Co., ltd and had a molecular weight of 600g/mol. The antioxidant is prepared by mixing BASF1010 and BASF168 according to a weight ratio of 1:1. Mixing the raw materials in a high-speed stirrer for 5min, melting the obtained mixture by a double-screw extruder, extruding and granulating to obtain the composition.
The resulting composition was processed into film articles by blow molding, and the specific production conditions and film properties are shown in Table 1.
Comparative example 5
Polybutylene terephthalate-polybutylene succinate copolymer (PBST) and talcum powder are mixed according to the weight ratio of 99:1, and then 0.1 weight percent of chain extender, 5 weight percent of glycerol and 0.3 weight percent of antioxidant are added into the mixture. The weight percentages of the chain extender, the glycerol and the antioxidant are calculated according to the sum of the weight of PBST and the weight of talcum powder. Wherein, the polybutylene terephthalate-polybutylene succinate copolymer (PBST) is a pilot-scale product of Beijing chemical industry research institute, and the molar content of the repeating unit (II) is 50 percent. Talc powder is from Michelin Corp, 5000 mesh. The chain extender is BASF corporationADR 4468. Glycerol is available from Shanghai Ala Biochemical technologies Co. The antioxidant is prepared by mixing BASF1010 and BASF168 according to a weight ratio of 1:1. Mixing the raw materials in a high-speed stirrer for 5min, melting the obtained mixture by a double-screw extruder, extruding and granulating to obtain the composition.
The resulting composition was processed into film articles by blow molding, and the specific production conditions and film properties are shown in Table 1.
TABLE 1
Note that: MD stands for machine direction and TD stands for transverse direction.
As can be seen from Table 1, the addition of talc powder to the composition of the present invention can raise the crystallization temperature of PBST to 20 deg.C or higher, thus significantly increasing the crystallization solidification rate of the melt, increasing the production speed, and simultaneously improving the stability of the film, avoiding the problems of collapse and wrinkling, etc., and avoiding adhesion. In addition, the addition of talcum powder can also improve the mechanical strength of PBST film products and remarkably improve the processing rate. The content and the grain diameter of talcum powder are in a range which can meet the requirements of rapid processing and stable film, and the obtained film has better balance of rigidity and toughness. Beyond this range, the above-mentioned features are not provided. The polyethylene glycol has the function of obviously improving the breaking elongation of the material, so that the film has good toughness and is not easy to break. It can be seen that the material has a good balance of stiffness and toughness within the required compositional range.
The foregoing description of embodiments of the invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described.