CN113980435B

CN113980435B - PBT resin with low dyne value and preparation method thereof

Info

Publication number: CN113980435B
Application number: CN202111563070.4A
Authority: CN
Inventors: 王尹杰; 申维新; 石景丽; 岳同健
Original assignee: Shanghai Sunny Technology Co ltd
Current assignee: Shanghai Sunny Technology Co ltd
Priority date: 2021-12-20
Filing date: 2021-12-20
Publication date: 2023-07-18
Anticipated expiration: 2041-12-20
Also published as: CN113980435A

Abstract

The invention provides a low-dyne PBT resin and a preparation method thereof, wherein the low-dyne PBT resin comprises the following components in parts by weight: 100 parts of polybutylene terephthalate (PBT); 8-20 parts of polypropylene GMA graft; 0.5-2 parts of crystallization inhibitor; 0.01-0.05 part of catalyst. The preparation method of the low-dyne PBT resin comprises the following steps: s1, weighing the components according to the weight ratio: 100 parts of polybutylene terephthalate, 8-20 parts of polypropylene GMA graft, 0.5-2 parts of crystallization inhibitor and 0.01-0.05 part of catalyst. S2, fully and uniformly mixing the components in the step S1 by a high-speed mixer, extruding by a double-screw extruder, and granulating to obtain the PBT resin with a low dyne value. The low-dyne PBT resin has a dyne value lower than 38, has no precipitation risk, and can be applied to the fields of PCB packaging and the like requiring low-dyne application.

Description

PBT resin with low dyne value and preparation method thereof

Technical Field

The invention relates to the technical field of high polymer materials, in particular to a low-dyne PBT resin and a preparation method thereof.

Background

A printed circuit board (Printed Circuit Board, abbreviated as PCB) is formed on a general-purpose substrate in a predetermined design. In the PCB manufacturing process, a lamination (e.g. a cover film, PI film, pure plastic steel sheet, etc.) operation usually uses a release film for protection and isolation. At present, after high-temperature lamination, silicone oil transfer with different degrees can be generated by common organosilicon release films in the prior art, and residual silicone oil or vaporific substances are present on the surface of the release films, so that the peeling strength of the lamination surface of the subsequent process is reduced or even does not reach the standard. The non-silicon release materials are mainly TPX, PTFE, FEP and the like, but the release materials with low dyne values are too high in price and are not suitable for being applied to pressing operation in batches.

Polybutylene terephthalate (PBT) is one of five major engineering plastics, a semi-crystalline engineering plastic. Has good mechanical property, electrical property, chemical resistance and the like, and has wide application in the fields of electronic appliances, automobiles and the like. However, the PBT has a large surface tension and is difficult to separate from the target, so that the PBT has limited application in the fields of films, especially PCB packaging and the like. Few reports have been made on low dyne PBT resins, such as in CN105440604a by adding adjuvants of the external lubricating type, such as: oxidized polyethylene wax, stearate, stearamide, etc. to reduce the dyne value of the PBT surface, but the effect of reduction is limited and the addition of large amounts involves a risk of precipitation.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a PBT resin with a low dyne value and a preparation method thereof. Can be applied to various fields of PBT application requiring low dyne value.

The invention aims at realizing the following scheme:

the first aspect of the invention provides a low-dyne PBT resin, which comprises the following components in parts by weight:

preferably, the polybutylene terephthalate (PBT) resin has a carboxyl end group content of 18-22 mol/t, preferably a PBT resin with a relatively high carboxyl end group content, and the reactivity with PP grafted GMA is increased.

Preferably, the polypropylene GMA graft is selected from SPG-02, a good-compatibility polymer (Shanghai) limited company.

Preferably, the crystallization inhibitor is a Cyclic Butylene Terephthalate (CBT) having the structural formula:wherein n is any integer between 2 and 7. CBT-100 manufactured by Saikx Co., USA may be selected.

Preferably, the catalyst is anhydrous ethylene glycol antimony (CAS: 29736-75-2), and ethylene glycol antimony produced by Yunnan Muli antimony Co., ltd.

The second aspect of the invention provides a preparation method of a low-dyne PBT resin, comprising the following steps:

s1, weighing the components according to the weight ratio: 100 parts of polybutylene terephthalate (PBT), 8-20 parts of polypropylene GMA graft, 0.5-2 parts of crystallization inhibitor and 0.01-0.05 part of catalyst.

S2, fully and uniformly mixing the components in the step S1 by a high-speed mixer, extruding by a double-screw extruder, and granulating to obtain the PBT resin with a low dyne value; the rotating speed of the twin-screw extruder is 450-600 rpm, and the temperature is 230-240 ℃.

The prepared PBT resin has a dyne value lower than 38, has no precipitation risk, and can be applied to the fields of PCB packaging and the like requiring low dyne value application.

Compared with the prior art, the invention has the following beneficial effects:

1. the low-dyne PBT resin has a dyne value lower than 38, has no precipitation risk, and can be applied to the fields of PCB packaging and the like requiring low-dyne application.

2. In the PBT resin prepared by the method, the PBT resin with high carboxyl content and the polypropylene grafted GMA are used, and then ethylene glycol antimony is introduced into the system as a reaction catalyst, so that the GMA group and the PBT resin are fully reacted, the reactivity between the GMA group and the PBT resin is improved, the compatibility between the polypropylene and the PBT resin is increased, and the polypropylene resin with low dyne value characteristic can fully reach the surface, thereby reducing the dyne value of the composite material.

3. The PBT resin prepared by the method is a semi-crystalline resin with coexisting crystalline and amorphous states, and because the cyclic polybutylene terephthalate (CBT) is introduced as a crystallization inhibitor, the reaction efficiency between the PP grafted GMA and the PBT resin is improved, the molecular chain length of the PBT is expanded, thereby reducing the crystallinity of the PBT resin, reducing the surface crystalline state content in the process of forming and cooling the PBT, and further reducing the dyne value of the PBT resin. Meanwhile, the CBT resin has extremely strong reactivity, and can 'kill' residual carboxyl end, hydroxyl end, GMA and other high-polarity groups.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications could be made by those skilled in the art without departing from the inventive concept. These are all within the scope of the present invention.

The PBT resin prepared by the invention utilizes the low-dyne characteristic of polypropylene to reduce the surface dyne of the PBT resin, however, the simple use of polypropylene grafted GMA can not effectively reduce the dyne of the PBT resin, mainly because the compatibility of the PBT resin and PP is insufficient, the PP resin can not be fully dispersed on the surface of a matrix, and meanwhile, a high-polarity GMA group exists, so that the GMA group and the PBT resin need to be fully reacted.

But the PBT resin has stable structure and low reactivity. Therefore, when the PBT resin with high carboxyl content is used, ethylene glycol antimony is introduced into the system as a catalyst for reaction, so that the reactivity between the ethylene glycol antimony and the PBT resin is improved, the compatibility between polypropylene and the PBT resin is increased, and the polypropylene resin with low dyne value characteristic can fully reach the surface, thereby reducing the dyne value of the composite material.

Since the PBT resin is a semi-crystalline resin with coexisting crystalline and amorphous states, the crystalline state has a higher density than the amorphous state, so that the crystalline state has a higher dyne value than the amorphous state, and therefore, the cyclic polybutylene terephthalate (CBT) is introduced as a crystallization inhibitor, the CBT resin has high reactivity, the crystallization of the PBT molecular chain is reduced, the reaction efficiency between the PP grafted GMA and the PBT resin is improved, the length of the PBT molecular chain is increased, the crystallization degree of the PBT resin is reduced, the surface crystalline state content is reduced, and the dyne value of the PBT resin is further reduced in the PBT molding cooling process. Meanwhile, the CBT resin has extremely strong reactivity, and can 'kill' residual carboxyl end, hydroxyl end, GMA and other high-polarity groups.

The technical scheme of the present invention is described in detail below in connection with specific embodiments.

The PBT resin used in the following examples has a carboxyl end group content of 18 to 22mol/t and is obtained from PBT KH2083 produced by Kapsinization of Yingkou.

The terminal carboxyl group of the PBT resin used in the comparative example was 10-11mol/t, and was purchased from PBT TH6100 produced by Xinjiang blue mountain Tun river.

The polypropylene grafted GMA used in examples 1-5 and comparative examples 1-5 was purchased from SPG-02 manufactured by Shanghai polymers Co.

The crystallization inhibitors employed in examples 1-5 and comparative examples 1-5 were branched polyesters, available from CBT-100 of Saikx, wikipedia.

The catalyst used in examples 1-5 and comparative examples 1-5 was ethylene glycol antimony, available from Yunnan Muli antimony Co.

The method for testing the dyne value is as follows:

(1) Selecting a dyne pen (such as specifications of 29, 30, 31, 32, 33, 34, 36, 38, 40, 42, 46, 48, 50 and the like) with a corresponding pen number according to test requirements, and ensuring whether the dyne pen is worn with an electrostatic ring and a finger stall within the service life;

(2) Finding out a test area according to the test requirement to ensure that the surface is clean and free of particles/dirt;

(3) Vertically holding the dyne pen, and vertically testing the surface of the dyne pen; immediately drawing the pen after the pen point is lightly pressed to start drawing a straight line of 5-10 cm, and covering a pen cap;

(4) After 2-5s, visually observing whether the handwriting shrink and agglomerate into water drop points:

a: if the water drop is contracted, the level-one value of the dyne pen is changed down, and then a straight line is drawn until the water drop is not contracted and no water drop point exists, so that the surface dyne value of the material is determined.

B: if the handwriting is smooth and is not condensed into a water drop point, the dyne pen with the higher numerical value is changed to draw a straight line again until the handwriting is shrunk and is condensed into the water drop point, and the dyne pen number of the last numerical value is the surface dyne value of the material.

Example 1

The PBT resin with the low dyne value comprises the following components in parts by weight:

the preparation method of the PBT resin comprises the following steps:

(1) Weighing the following components in parts by weight: polybutylene terephthalate (PBT), polypropylene GMA graft, crystallization inhibitor and catalyst.

(2) Fully and uniformly mixing the components in the step (1) by a high-speed mixer, extruding by a double-screw extruder, and granulating to obtain the PBT resin with a low dyne value; the rotating speed of the twin-screw extruder is 450-600 rpm, and the temperature is 230-240 ℃.

And (3) injection molding the prepared PBT resin into a standard test template, wherein the size of the standard test template is 10cm multiplied by 2cm, drawing a print on the template by using a dyne pen, and testing the dyne value of the template according to print shrinkage.

Example 2

the preparation method is the same as in example 1.

Example 3

the preparation method is the same as in example 1.

Example 4

the preparation method is the same as in example 1.

Example 5

the preparation method is the same as in example 1.

Comparative example 1

PBT KH2083 is molded into a standard test template with the dimensions of 10cm multiplied by 2cm, a print is drawn on the template by a dyne pen, and the dyne value of the template is tested according to the shrinkage of the print.

Comparative example 2

Unlike example 3, polybutylene terephthalate (PBT) was selected from PBT TH6100.

Comparative example 3

Unlike example 4, no polypropylene graft GMA SPG-02 was added.

Comparative example 4

Unlike example 2, the crystallization inhibitor CBT 100 was not added.

Comparative example 5

Unlike example 5, no antimony glycol catalyst was added.

Test results

The results of the dyne value test of the materials prepared in examples 1 to 5 and comparative examples 1 to 5 are shown in Table 1:

table 1, examples 1 to 5 and comparative examples 1 to 5, and results of the test

From the data in Table 1, it can be seen that the low dyne PBT prepared by the present invention has a dyne value of 38 or less.

Comparative example 1 shows that the pure PBT resin has a higher dyne value, and examples 1-5 show that the PBT dyne value is significantly reduced after the method is adopted. Comparative example 2 and example 1 show that the PBT resin with high molar carboxyl content has higher reactivity with the PP graft and is more effective in reducing the surface dyne value. Comparative example 3 shows that without the addition of SPG-02, more polar groups remain on the surface due to the catalytic action of ethylene glycol antimony, resulting in a higher dyne value for the material. Comparative example 4 shows that the main effect of CBT is crystallization inhibition and "annihilation" of reactive groups, and that the material's dyne value cannot be effectively reduced without CBT groups; comparative example 5 shows that ethylene glycol antimony is mainly used for catalyzing PBT to generate more reactive groups, and improves the reactivity of the low-reactivity PBT resin with SPG-02.

The foregoing describes specific embodiments of the present invention. It is to be understood that the invention is not limited to the particular embodiments described above, and that various changes or modifications may be made by those skilled in the art within the scope of the appended claims without affecting the spirit of the invention. The embodiments of the present application and features in the embodiments may be combined with each other arbitrarily without conflict.

Claims

1. The PBT resin with the low dyne value is characterized by comprising the following components in parts by weight:

wherein the carboxyl end group content of the polybutylene terephthalate is 18-22 mol/t; the method comprises the steps of carrying out a first treatment on the surface of the The PBT resin with low dyne value is semi-crystalline resin; the crystallization inhibitor is a branched polyester; the branched polyester is annular butylene terephthalate; the catalyst is anhydrous ethylene glycol antimony.

2. The low dyne PBT resin of claim 1, wherein the annular butylene terephthalate has the following structural formula:wherein n is any integer between 2 and 7.

3. A process for preparing a low dyne PBT resin of claim 1, comprising the steps of:

s1, weighing the components according to the weight ratio: 100 parts of polybutylene terephthalate, 8-20 parts of polypropylene GMA graft, 0.5-2 parts of crystallization inhibitor and 0.01-0.05 part of catalyst;

s2, after uniformly mixing the components in the step S1, extruding and granulating to obtain the PBT resin with a low dyne value.

4. The process for producing a low-dyne PBT resin according to claim 3, wherein the twin-screw extruder used for extrusion pelletization has a rotation speed of 450 to 600 rpm and a temperature of 230 to 240 ℃.