CN-116622059-B - Polybutylene succinate and polysiloxane block copolymer and preparation method thereof

CN116622059BCN 116622059 BCN116622059 BCN 116622059BCN-116622059-B

Abstract

The invention provides a poly (butylene succinate) and polysiloxane block copolymer and a preparation method thereof, by introducing polysiloxane blocks with good biocompatibility and biological stability and wide sources into poly (butylene succinate), the preparation of the poly (butylene succinate) and polysiloxane block copolymer solves the problems of low impact strength, lack of functionality and the like of poly (butylene succinate) homopolymers. The polybutylene succinate and the polysiloxane block copolyesters have excellent mechanical properties and high molecular weight, and the polysiloxane blocks also endow the block copolyesters with good anti-fouling function and excellent impact resistance, and simultaneously improve the tensile strength, bending strength and elongation at break.

Inventors

ZHENG LIUCHUN
ZHOU TIANBO
WANG HAOLIANG
LIU YI

Assignees

沧州市天津工业大学研究院

Dates

Publication Date: 20260512
Application Date: 20230524

Claims (7)

1. The preparation method of the polybutylene succinate and polysiloxane block copolymer is characterized by comprising the following steps of: (1) Mixing dimethyl succinate, butanediol and polysiloxane, and carrying out transesterification reaction in the presence of a transesterification catalyst to obtain a transesterification product; (2) Mixing the reaction product with a polycondensation catalyst, and performing polycondensation reaction to obtain a block copolymer; Wherein the polysiloxane block comprises polysiloxanes with different molecular chain lengths and with molecular weights of 1000-12000 g/mol; The transesterification catalyst comprises one or more of inorganic metal acetate, organic titanium compound and phosphorus-containing compound, the polycondensation catalyst comprises a mixture of phosphorus-containing compound and organic titanium compound, the mass of the transesterification catalyst is 0.002-3% of the sum of the mass of dimethyl succinate and the mass of butanediol, the mass of the polycondensation catalyst is 0.005-3% of the sum of the mass of butanediol dimethyl ester, the mass of butanediol and the mass of polysiloxane, the polysiloxane comprises one of polysiloxane PDMSa, polysiloxane PDMSb and polysiloxane PDMSc, and the chemical structural formula of PDMSa is shown as formula (I): Formula (I) Wherein n is 10-120, and the chemical structural formula of the PDMSB is shown as formula (II): Formula (II) Wherein n is 10-80, m is 4-10; PDMSc has a chemical structural formula shown in formula (III): formula (III) Wherein n is 5-80, m is 1-16.
2. The method of claim 1, wherein the molar ratio of the repeating units of the polysiloxane segment to the dimethyl succinate units in the block copolymer is 1:2.5 to 1:20.
3. The preparation method according to claim 1, wherein the inorganic metal acetate comprises one or more of antimony acetate, magnesium acetate and zinc acetate, the organic titanium compound comprises alkyl titanium with total carbon atoms of 4-40 and/or alkoxy titanium with total carbon atoms of 4-40, and the phosphorus-containing compound comprises one or more of phosphoric acid, trimethyl phosphate, triethyl phosphate, tributyl phosphate and tripropyl phosphate.
4. The preparation method according to claim 1, wherein when the transesterification catalyst is a mixture of inorganic acetate and organic titanium compound, the mass ratio of the inorganic acetate to the organic titanium compound is 0.2-1:1, and when the polycondensation catalyst is a mixture of phosphorus-containing compound and organic titanium compound, the mass ratio of the phosphorus-containing compound to the organic titanium compound is 0.05-1.5:1.
5. The method of claim 1, wherein the molar ratio of dimethyl succinate to butanediol is 1:1-1:2.5.
6. The method according to claim 1, wherein the transesterification reaction is carried out at a pressure of 10 to 120 kPa, a temperature of 110 to 190℃and a time of 1 to 3 hours, the polycondensation reaction is carried out at a pressure of 20 to 500 Pa, a temperature of 170 to 250℃and a time of 1 to 3 h.
7. A polybutylene succinate and polysiloxane block copolymer prepared according to the preparation method of any one of claims 1-6, characterized in that the block copolymer is a block copolyester having a weight average molecular weight of more than 200000.

Description

Polybutylene succinate and polysiloxane block copolymer and preparation method thereof Technical Field The invention relates to the field of high polymer material synthesis, in particular to a polybutylene succinate and polysiloxane block copolymer and a preparation method thereof. Background The white pollution caused by conventional plastics has prompted the rapid development of biodegradable plastics. Among the biodegradable polymer materials, polybutylene succinate has been widely paid attention to due to its excellent comprehensive properties, and is one of the most promising biodegradable materials. The melting point (T m) of the polybutylene succinate is 110-116 ℃, the thermal decomposition temperature is higher than (T d) and is higher than 350 ℃, the polybutylene succinate has good thermal stability, and the mechanical property of the polybutylene succinate is close to that of low-density polyethylene and polypropylene, so that the polybutylene succinate can meet the use requirement of general plastics. In addition, the polybutylene succinate is stable in a dry environment and can be completely degraded in a composting environment. However, compared with other traditional non-degradable high polymer materials, the polybutylene succinate still has the defects of high price, lack of functionality, poor mechanical property and the like, particularly has poor impact strength, and is difficult to meet the requirement on the material performance in practical application. Therefore, by designing the molecular structure of the biodegradable material and introducing the copolymerization unit, the improvement of various properties of the polybutylene succinate and the endowment of the polybutylene succinate with the functionality become the focus of research at the present stage. Random copolymerization is simple and easy to implement and is commonly used for copolymerization modification of high polymers, but the random copolymerization damages a molecular chain structure of the polybutylene succinate, reduces crystallization performance of the polymer, improves shock resistance of the material, and obviously reduces melting point, tensile strength and bending strength of the material due to larger negative influence of random copolymerization on crystallization capability of the material. The block copolymer can make the material possess the advantages of two homopolymers, and can not destroy the crystallization property of the crystallization chain segment, and can not cause great reduction of crystallinity, and can not lose the thermal property and mechanical property of the material. At the present stage, polyether molecular chains, succinic acid and butanediol are mainly adopted to synthesize the polybutylene succinate segmented copolymer, however, the polyether block contains a large amount of ether bonds, so that the thermal stability of the polyester material is obviously reduced, and meanwhile, the tensile strength and bending strength of the product are greatly reduced due to the flexibility of the polyether chain segment. Compared with polyether blocks, polysiloxanes have good thermal stability and oxidation resistance due to their unique organic and inorganic structures, outstanding chemical inertness, low temperature resistance, anti-icing, biocompatibility and biostability, and it has been reported that polycarbonates, polyurethanes and petroleum-based polyesters have been modified by introducing polysiloxane segments of different pendant and terminal groups. CN115124707 a discloses a method for modifying polycarbonate by polysiloxane containing phosphorus side group, the invention introduces polysiloxane chain segment into polycarbonate molecular chain by copolymerization mode, and obtains a phosphorus-containing silicon copolycarbonate with chemical resistance and good low temperature shock resistance. Li Zhen et al (Biomacromolecules 2018,19, 2137-2145) incorporate polysiloxanes as soft segments into polyurethanes to promote their hydrolysis and oxidation resistance. Patent CN111748279a discloses a method for modifying polyethylene terephthalate by polysiloxane block and fluorine-containing glycol, which prepares modified polyester with high weather resistance and high anti-fouling property, and is used in the fields of paint, color coated plate and the like. At present, research reports of preparing a block copolymer by introducing polysiloxane blocks into biodegradable polyester polybutylene succinate are not yet seen. At present, the poly (butylene succinate) is generally prepared by esterification and polycondensation of succinic acid and butylene glycol, a byproduct of the poly (butylene succinate) is water, and the water is easy to crosslink a polysiloxane block, so that the surface functionality of the material is reduced, and no solution is given in the literature concerning the problem. In view of this, the present invention has been made. Disclosure of Invention The invention aims