1. A process for the crystallization of crystalline form III from isotactic poly-1-butene in bulk, characterized in that it is carried out according to the following steps: blending isotactic polybutene-1, an antioxidant and an additive to disperse uniformly, heating and melting, extruding and granulating to obtain isotactic polybutene-1 granules containing a crystal form III structure, wherein: 100 parts of isotactic polybutene-1, 0.3-0.5 part of antioxidant and 1-3 parts of dendritic hyperbranched polyester as additive.

2. The process according to claim 1 for the crystallization of crystalline form III from the bulk of isotactic polybutene-1, wherein the isotactic polybutene-1 has a number average molecular weight of 27.4 x 10⁵g/mol, molecular weight distribution5.5。

3. The method for producing the crystal form III through the crystallization from the isotactic poly-1-butene bulk according to claim 1, wherein the antioxidant is prepared from antioxidant 168 and antioxidant 1098 in a mass ratio of 2: 1 addition.

4. The method for producing crystalline form III by crystallization from isotactic poly-1-butene in bulk according to claim 1, wherein the dendritic hyperbranched polyester as additive is aliphatic hyperbranched polyester hyper H104.

Background

Isotactic poly-1-butene (iPB-1) is a polymer obtained by polymerizing 1-butene as a raw material with or without addition of a comonomer under a specific catalyst system. Poly-1-butene is one of typical polymorphic polymer representatives and has five crystal structures of I, I ', II' and III. Form III exhibits an orthorhombic unit cell structure built up from 4/1 helices, and is typically prepared by solution crystallization. It would therefore be of great interest if a process could be developed that efficiently crystallizes directly from the bulk of isotactic poly-1-butene to form III. The prior art shows that the crystal form III can be directly obtained by solution crystallization, matrix epitaxial growth and other methods, the melting point of the crystal form III is about 98 ℃, but no report shows that the crystal form III can be directly obtained by crystallization from an isotactic poly-1-butene body.

Disclosure of Invention

The invention aims to make up the defects of the existing preparation technology of the crystal form III, provides a method for directly crystallizing the crystal form III from an isotactic poly-1-butene body, and provides a feasible way for directly crystallizing the crystal form III from the isotactic poly-1-butene body by adding a proper additive.

The technical purpose of the invention is realized by the following technical scheme.

A process for the crystallization of crystalline form III from isotactic poly-1-butene in bulk, according to the following steps: blending isotactic polybutene-1, an antioxidant and an additive to disperse uniformly, heating and melting, extruding and granulating to obtain isotactic polybutene-1 granules containing a crystal form III structure, wherein: 100 parts of isotactic polybutene-1, 0.3-0.5 part of antioxidant and 1-3 parts of dendritic hyperbranched polyester as additive.

Furthermore, the number average molecular weight of isotactic polybutene-1 was 27.4X 10⁵g/mol, molecular weight distribution 5.5.

And the antioxidant is prepared from antioxidant 168 and antioxidant 1098 according to the mass ratio of 2: 1 addition.

Moreover, the dendritic hyperbranched polyester as the additive is aliphatic hyperbranched polyester hyper H104.

The technical method provided by the invention is suitable for iPB-1, generally, the crystal form III can be obtained only by solution crystallization, but the crystal form III can be obtained by direct crystallization from a body by adopting the technical method provided by the invention, and the existence of the structure of the crystal form III is proved by DSC and WAXD tests.

Drawings

Figure 1 is a DSC melting plot of samples containing form I and form III according to the present invention.

Figure 2 is a DSC melting curve for samples of the invention containing form II and form III.

FIG. 3 is a 1D-WAXD plot of samples containing form II and form III of the present invention.

FIG. 4 is a 1D-WAXD plot of samples containing form I and form III of the present invention.

Detailed Description

The present invention will be described in further detail with reference to specific examples.

100 portions of isotactic polybutene-1 powder (Shandong Oriental Macro chemical Co., Ltd., number average molecular weight 27.4X 10)⁵g/mol, molecular weight distribution of 5.5, each part is 1g), 0.5 part of antioxidant (antioxidant 168 and antioxidant 1098 according to the mass ratio of 2: 1, 1g of new Tianjin Lianlong material company, 1g of each part, 3 parts of dendritic hyperbranched polyester (Wuhan hyperbranched resin technology company, hyper H104 aliphatic hyperbranched polyester, 1g of each part) as an additive, blending, and extruding and granulating by using a double-screw extruder (SHJ-20B, Nanjing Jie Ente) to obtain isotactic polybutene-1, wherein the temperature of the extruder is set as follows, one area: 140 ℃; and a second zone: 170 ℃; and (3) three zones: 180 ℃; and (4) four areas: 180 ℃; and a fifth zone: 180 ℃; a sixth zone: 180 ℃; seven areas: 180 ℃; and eight regions: 180 ℃ is carried out.

Weighing 7mg of sample, placing the sample into an aluminum crucible, placing the crucible into DSC (LNP95, Linkam) equipment, raising the temperature to 150 ℃ at 10 ℃/min and keeping the temperature for 5min, then lowering the temperature to 30 ℃ at 30 ℃/min, raising the temperature to 150 ℃ again at 10 ℃/min and keeping the temperature for 5min, wherein the melting curves obtained in the two temperature raising processes are shown in figures 1 and 2. The first temperature rise process is a process of eliminating heat history, and a melting peak at 98 ℃ can be observed through a melting curve of the sample as shown in fig. 1, and a melting curve obtained through the second temperature rise as shown in fig. 2 can be observed at 98 ℃. The two melting peaks (98-99 ℃) at about 98 ℃ are the melting peak of the crystal form III, which indicates that the crystal form III is generated.

Putting a proper amount of sample into a shear hot table, heating to 150 ℃ at a speed of 10 ℃/min, keeping the temperature for 5min, then cooling to 30 ℃ at a speed of 30 ℃/min to obtain a sheet sample, and immediately carrying out WAXD test under the conditions that: the wavelength is 0.154nm, the scanning range is 5-30 degrees, the scanning speed is 6 degrees/min, after a sample sheet is prepared, a WAXD test is immediately carried out, a 1D-WAXD graph 3 obtained by a scanning curve is obtained, a peak at a position of 2 theta (11.9 degrees) represents diffraction peaks of a crystal form II and a crystal form III, and because the distance is short and the content of the crystal form III is less, the diffraction peaks of the crystal form II and the crystal form III coincide; the sheet sample was allowed to stand at room temperature for two weeks, and subjected to WAXD test again under the same conditions, and the obtained 1D-WAXD was shown in fig. 4, in which the peak at 2 θ ═ 12.5 ° represents the diffraction peak of form III, the peak at 2 θ ═ 10.0 ° represents the diffraction peak of form I, and form I was converted from form II over a period of two weeks.

According to the content of the invention, after an antioxidant and an additive are added into iPB-1 powder, the mixture is extruded and granulated to obtain the iPB-1 material containing a crystal form III structure. DSC and WAXD tests prove that the crystal form III can be directly crystallized from the isotactic poly-1-butylene body. The invention has been described in an illustrative manner, and it is to be understood that any simple variations, modifications or other equivalent changes which can be made by one skilled in the art without departing from the spirit of the invention fall within the scope of the invention.