CN114874405A - Thermoplastic phenolic resin and preparation process thereof - Google Patents
Thermoplastic phenolic resin and preparation process thereof Download PDFInfo
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- CN114874405A CN114874405A CN202210613794.3A CN202210613794A CN114874405A CN 114874405 A CN114874405 A CN 114874405A CN 202210613794 A CN202210613794 A CN 202210613794A CN 114874405 A CN114874405 A CN 114874405A
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G8/00—Condensation polymers of aldehydes or ketones with phenols only
- C08G8/04—Condensation polymers of aldehydes or ketones with phenols only of aldehydes
- C08G8/08—Condensation polymers of aldehydes or ketones with phenols only of aldehydes of formaldehyde, e.g. of formaldehyde formed in situ
- C08G8/10—Condensation polymers of aldehydes or ketones with phenols only of aldehydes of formaldehyde, e.g. of formaldehyde formed in situ with phenol
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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Abstract
The application discloses a thermoplastic phenolic resin and a preparation process thereof, wherein the preparation process comprises the following steps: step S100, mixing a phenolic compound and a catalyst, and heating to a preset value to obtain a system A; s200, dropwise adding a formaldehyde solution into the system A to react, dehydrating the reaction system at the same time, and obtaining a system B after the reaction is finished; step S300, after the reaction is finished, dehydrating and dephenolizing the system B; and S400, cooling and discharging. According to the preparation method, the reaction and the dehydration are carried out simultaneously, and the heat generated by the condensation reaction is used for dehydration, so that the preparation time of the thermoplastic phenolic resin is shortened, the production energy consumption is effectively reduced, the energy-saving and emission-reducing effects are achieved, and the production cost is reduced.
Description
Technical Field
The application relates to the technical field of high polymer materials, in particular to thermoplastic phenolic resin and a preparation process thereof.
Background
The thermoplastic resin is usually an organic polymer compound obtained by condensing formaldehyde and an excess amount of phenol in the presence of an acid catalyst. In the production of thermoplastic resins, a 37 wt% aqueous formaldehyde solution is generally used, resulting in the introduction of a large amount of moisture, and water is produced during the condensation reaction of formaldehyde and phenol, and therefore, dehydration is required to obtain the final thermoplastic resin.
In the existing preparation process, after the reaction of formaldehyde and phenol is finished, moisture is usually removed through a normal pressure or reduced pressure mode, but a large amount of energy and time are consumed, particularly in industrial production, the volume of a reaction kettle is 10-20 cubic, a large amount of water exists after the reaction is finished and needs to be removed, and the reason for long dehydration time mainly comprises the following steps: (1) the volatilization channel of the reaction kettle is small, (2) under the condition that water exists, the temperature in the reaction kettle is basically 100 ℃, so that the viscosity of resin in the reaction kettle is high, and the dehydration difficulty is increased; (3) in order to avoid the denaturation of the thermoplastic resin, high-pressure steam is mostly adopted in production workshops for heating, and the temperature is 160-170 ℃, so that the dehydration rate is influenced.
Disclosure of Invention
In view of the above problems, the present application provides a phenol novolac resin and a process for preparing the same.
In the application, the preparation process of the thermoplastic phenolic resin comprises the following steps:
step S100, mixing a phenolic compound and a catalyst, and heating to a preset value to obtain a system A;
s200, dropwise adding a formaldehyde solution into the system A to react, and dehydrating the reaction system at the same time to obtain a system B after the reaction is finished;
step S300, after the reaction is finished, dehydrating and dephenolizing the system B;
and S400, cooling and discharging to obtain the thermoplastic phenolic resin.
Different from the existing preparation process, the method is to carry out reaction and dehydration (step S200), because the phenolic compound and formaldehyde in the formaldehyde solution are subjected to condensation reaction under the action of the catalyst, the condensation reaction is an exothermic process and can produce water, the method fully utilizes the heat in the exothermic process to evaporate (volatilize) water, and when the reaction is finished, namely the formaldehyde is basically reacted, the expected dehydration effect is achieved.
In order to avoid dewatering and take away a large amount of formaldehyde, the reaction rate of the formaldehyde and the phenolic compound and the mode of adding the formaldehyde are controlled, in the step S100, the preset value is the ideal temperature at which the formaldehyde and the phenolic compound can react quickly, in the step S200, the dripping mode is adopted, the dripping amount of the formaldehyde in unit time is controlled, the formaldehyde dripped in unit time is ensured to be quickly reacted, and the formaldehyde is prevented from being evaporated or taken away by water vapor. In addition, dehydration reduces the product water, thereby breaking the reaction balance and facilitating the condensation reaction.
And (5) continuously dehydrating the system B obtained in the step (S300) to further remove residual moisture in the system B, then dephenolizing, cooling and discharging to obtain the high-purity thermoplastic resin (step S400).
Optionally, the phenolic compound is a preheated molten phenolic compound.
Optionally, the catalyst is an acid catalyst, preferably a strong acid catalyst, which is beneficial to increasing the reaction rate of the phenolic compound and formaldehyde, so that the formaldehyde can be quickly utilized by being dripped into the reaction kettle, and the loss of the formaldehyde in dehydration is effectively reduced.
Optionally, the acid catalyst is at least one of oxalic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid and sulfuric acid.
Optionally, the phenolic compound is phenol, and the formaldehyde solution is an aqueous formaldehyde solution, for example, an aqueous formaldehyde solution with a mass concentration of 37 wt%.
Optionally, the molar ratio of the phenolic compound to formaldehyde is 1: 0.5 to 0.9.
Optionally, the mass ratio of the catalyst to the phenol is 0.2-5: 100.
optionally, in step S200, the dehydrating includes: and (4) dropwise adding formaldehyde from the beginning, and keeping the temperature for 20-40 min after dropwise adding is finished.
Optionally, in step S200, the dehydrating includes: and (4) dropwise adding formaldehyde from the beginning, and keeping the temperature for 30min after the dropwise adding is finished.
In the step S300, continuing to dehydrate after the heat preservation is finished, and finishing the dehydration till the temperature is 160-170 ℃, wherein the dehydration temperature is higher than the dehydration temperature in the step S200;
the dehydration in step 200 and step 300 is atmospheric dehydration.
Optionally, in step S100, the predetermined value is 110 to 140 ℃;
in the step S200, the dripping time of the formaldehyde solution is 1-3h, and the dehydration temperature is 110-140 ℃.
Under the condition that the preset value is 110-140 ℃, formaldehyde is dripped into the reaction kettle to rapidly perform condensation reaction with the phenolic compound, the dripping speed of the formaldehyde is controlled according to the reaction speed of the formaldehyde and the phenol, so that the reaction speed of the formaldehyde in unit time and the dewatering speed of the dripping speed are balanced, namely the dripping amount of the formaldehyde in unit time is consistent with the reaction amount, and water in the reacted formaldehyde aqueous solution is removed from the reaction kettle in the normal-pressure dewatering process. In addition, a large amount of heat can be released in the reaction process of the formaldehyde and the phenol, and the heat can be beneficial to quickly removing water in the formaldehyde, so that the energy utilization rate is improved. In addition, under the condition of 110-140 ℃, the water content in the reaction kettle is low, the viscosity of the reaction kettle is low, and water in the formaldehyde can be quickly removed.
Taking a 10-cube reaction kettle as an example, in the existing preparation process, the heat preservation reflux of phenol and formaldehyde needs 3 hours, the reaction is finished, then the normal pressure dehydration needs 5 hours to 120 ℃, the normal pressure dehydration needs 2 hours to 150 ℃, the pressure reduction dephenolization needs 2 hours, and the total time is 12 hours. In the application, formaldehyde is dripped for 3 hours while formaldehyde is dripped and dehydration is carried out at normal pressure at 120 ℃, 2 hours are needed from 120 to 150 ℃ after the dripping is finished, phenol is removed under reduced pressure for 2 hours, and the total time is 7 hours. The reaction efficiency is improved by about 1 time.
For another example, in a 2 cubic reaction kettle, the total preparation time of the thermoplastic phenolic resin is not more than 6.5h, and the production efficiency is more than 200 kg/h.
Optionally, in step S300, the dephenolization mode is vacuum dephenolization.
Optionally, the vacuum dephenolization conditions are as follows: the vacuum degree is less than-0.095 Mpa, and the temperature is 170-180 ℃.
Optionally, in step S200, the dehydration is distillation.
Optionally, in step S200, the manner of adding formaldehyde dropwise and dehydrating simultaneously is as follows: in the process of dripping formaldehyde, switching the reaction kettle into a distillation state; referring to fig. 1, the reaction kettle has at least two ports, wherein one port is connected with a formaldehyde dripping tank for dripping formaldehyde; another opening is connected with the condenser, and when the in-process at dropwise add formaldehyde, the opening that reation kettle and condenser are connected is opened, and the water of evaporation is deviate from the opening in the reation kettle to realize the while dropwise add formaldehyde and dewater.
The application also provides a thermoplastic phenolic resin prepared by adopting any preparation process of the thermoplastic phenolic resin.
Compared with the prior art, the preparation process provided by the application uses the heat generated by the condensation reaction for dehydration by simultaneously reacting and dehydrating, so that the preparation time of the thermoplastic phenolic resin is shortened, the production energy consumption is effectively reduced, the energy-saving and emission-reducing effects are achieved, and the production cost is reduced.
Drawings
FIG. 1 is a diagram of a process for preparing a thermoplastic phenolic resin in the present application.
Detailed Description
In order to facilitate a better understanding of the technical solutions of the present invention for those skilled in the art, the present invention will be further described with reference to the following specific examples, but the present invention is not limited thereto.
Example 1
(1) Adding 1500kg of preheated and molten phenol into a high-level metering tank by using a special pump, and metering to 2m 3 Adding 15kg of oxalic acid into the reaction kettle, and heating to 130 ℃ to obtain a system A;
(2) the reaction kettle is placed in a dehydration device state (normal pressure state), 1100kg of 37 wt% formaldehyde solution is dripped, and the dripping is completed within 3 hours; in the formaldehyde dripping process, according to the dehydration condition, controlling the temperature at 130 ℃, preserving heat for 30min after dripping is finished, and obtaining a system B after heat preservation is finished, wherein 900kg of water is removed;
(3) dehydrating the system B at the normal pressure, wherein the dehydration temperature is 170 ℃, the dehydration time is 2 hours, and then performing vacuum dephenolization, wherein the vacuum dephenolization temperature is 180 ℃, the vacuum degree is less than-0.095 Mpa, and the dephenolization time is 1 hour;
(4) after cooling and discharging, 1606kg of light yellow transparent solid resin was obtained, and the total reaction time was 6.5 hours.
Example 2
(1) Adding 1500kg of preheated and molten phenol into a high-level metering tank by using a special pump, and metering to 2m 3 Adding 3kg of p-toluenesulfonic acid into the reaction kettle, and heating to 120 ℃ to obtain a system A;
(2) the reaction kettle was placed in a state of a dehydration apparatus (normal pressure state), 788kg of a 37% formaldehyde solution was started to be dropped, and the dropping was completed within 1 hour. In the dropping process of the formaldehyde, according to the dehydration condition, controlling the temperature at 120 ℃, preserving the heat for 30min after the dropping is finished, obtaining a system B after the heat preservation is finished, and removing 600kg of water;
(3) dehydrating the system B at normal pressure until the temperature reaches 160 ℃, finishing dehydration for 2.5 hours, and then performing vacuum dephenolization at the temperature of 180 ℃, the vacuum degree of less than-0.095 Mpa, and the dephenolization time of 1 hour;
(4) after cooling and discharging, 1436kg of light yellow transparent solid resin is obtained, and the total reaction time is 5 hours.
Example 3
(1) Adding 1500kg of preheated and molten phenol into a high-level metering tank by using a special pump, and metering to 2m 3 In the reaction kettle, 5kg of dodecylbenzene sulfonic acid is addedRaising the temperature to 140 ℃ to obtain a system A;
(2) placing the reaction kettle in a dehydration device state (normal pressure state), starting to dropwise add 930kg of 37% formaldehyde solution, finishing dropwise adding within 2 hours, controlling the temperature to be 140 ℃ according to dehydration conditions in the formaldehyde dropwise adding process, preserving heat for 30min after dropwise adding is finished, obtaining a system B after heat preservation is finished, and removing 760kg of water;
(3) dehydrating the system B at normal pressure, wherein the dehydration temperature is 160 ℃, the dehydration time is 2.5 hours, and the vacuum dephenolization is carried out at the temperature of 180 ℃, the vacuum degree is less than-0.095 Mpa, and the dephenolization time is 1 hour;
(4) the product was discharged and cooled to yield 1596kg of pale yellow transparent solid resin for a total reaction time of 6 hours.
Example 4
(1) Adding 1500kg of preheated and molten phenol into a high-level metering tank by using a special pump, and metering to 2m 3 Adding 3kg of sulfuric acid into the reaction kettle, and heating to 130 ℃ to obtain a system A;
(2) placing the reaction kettle in a dehydration device state (normal pressure state), starting to dropwise add 1040kg of 37% formaldehyde solution, finishing dropwise adding within 2 hours, controlling the temperature at 130 ℃ according to dehydration conditions in the formaldehyde dropwise adding process, preserving heat for 30min after dropwise adding is finished, obtaining a system B after heat preservation is finished, and removing 850 kg;
(3) dehydrating the system B at the normal pressure, wherein the dehydration temperature is 170 ℃, the dehydration time is 2.5 hours, and then performing vacuum dephenolization, wherein the temperature is 180 ℃, the vacuum degree is less than-0.095 Mpa, and the dephenolization time is 1 hour;
(4) after cooling, 1577kg of a pale yellow transparent solid resin was obtained, the total reaction time being 6 hours.
Example 5
(1) Adding 1500kg of preheated and molten phenol into a high-level metering tank by using a special pump, and metering to 2m 3 Adding 3kg of sulfuric acid into the reaction kettle, and heating to 110 ℃ to obtain a system A;
(2) placing the reaction kettle in a dehydration device state (normal pressure state), starting to dropwise add 910kg of 37% formaldehyde solution, finishing dropwise adding within 3 hours, controlling the temperature to be 110 ℃ according to dehydration conditions in the formaldehyde dropwise adding process, and preserving heat for 30min after dropwise adding is finished; after the heat preservation is finished, obtaining a system B, and removing 700kg of water;
(3) and (3) dehydrating the system B at normal pressure at 160 ℃ for 2 hours, and then performing vacuum dephenolization at 180 ℃ and under the vacuum degree of less than-0.095 Mpa for 1 hour.
(4) Cooling and discharging to obtain 1550kg of light yellow transparent solid resin, and the total reaction time is 6.5 hours.
Comparative example 1
1000kg of preheated and melted phenol is added into a high-level metering tank by a special pump and metered into a 2m metering tank 3 10kg of oxalic acid is added into the reaction kettle, 730kg of formaldehyde solution with the concentration of 37 percent is added dropwise after the temperature is raised to 100 ℃, the dropwise addition is completed within 1 hour, and the reflux and heat preservation at 100 ℃ are carried out for 1.5 hours after the dropwise addition is completed. After the reflux heat preservation is finished, the normal pressure dehydration temperature is started to 160 ℃, the dehydration time is 5 hours, the vacuum dephenolization temperature is started to 180 ℃ (the vacuum degree is less than minus 0.095Mpa), and the vacuum dehydration time is 1 hour. The product was discharged and cooled to give 1066Kg of a pale yellow transparent solid resin, the total reaction time being 8.5 hours.
TABLE 1 comparison of resin index and yield for examples 1-5 and comparative example 1
Comparing the softening point, free phenol content, reactor usage, production time, throughput and production efficiency of the phenolic resins prepared in examples 1-5 and comparative example 1, it can be seen from table 1 that the production efficiency of examples 1-5 is higher than that of comparative example 1. Compared with comparative example 1, the production time of example 1 is short, the yield is high, the production efficiency is improved by 97%, and the yield and the productivity of the thermoplastic phenolic resin are greatly improved.
The above description of the embodiments is provided to facilitate understanding and use of the invention by those skilled in the art, and appropriate changes and modifications may be made by those skilled in the art to which the present invention pertains. Therefore, the present application is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present application should fall within the scope of the claims of the present application.
Claims (8)
1. The preparation process of the thermoplastic phenolic resin is characterized by comprising the following steps:
step S100, mixing a phenolic compound and a catalyst, and heating to a preset value to obtain a system A;
s200, dropwise adding a formaldehyde solution into the system A to react, and dehydrating the reaction system at the same time to obtain a system B after the reaction is finished;
step S300, after the reaction is finished, dehydrating and dephenolizing the system B;
and S400, cooling and discharging to obtain the thermoplastic phenolic resin.
2. The process according to claim 1, wherein the catalyst is a strong acid type catalyst;
the phenolic compound is phenol;
the formaldehyde solution is a formaldehyde aqueous solution;
the molar ratio of the phenolic compound to the formaldehyde is 1: 0.5 to 0.9;
the mass ratio of the catalyst to the phenol is 0.2-5: 100.
3. the process according to claim 1, wherein in step S200, the dehydration is: dripping formaldehyde from the beginning, and keeping the temperature for 20-40 min after finishing dripping;
in the step S300, continuing to dehydrate after the heat preservation is finished, and finishing the dehydration till the temperature is 160-170 ℃, wherein the dehydration temperature is higher than the dehydration temperature in the step S200;
the dehydration in step 200 and step 300 is atmospheric dehydration.
4. The preparation process according to claim 3, wherein in step S100, the predetermined value is 110 to 140 ℃;
in the step S200, the dripping time of the formaldehyde solution is 1-3h, and the dehydration temperature is 110-140 ℃.
5. The process according to claim 1, wherein in step S300, dephenolation is performed by vacuum dephenolation;
the vacuum dephenolization conditions are as follows: the vacuum degree is less than-0.095 Mpa, and the temperature is 160-180 ℃.
6. The process according to claim 1, wherein in step S200, the dehydration is carried out by distillation.
7. The process according to claim 6, wherein the dehydration is performed while adding formaldehyde in step S200 by: in the process of dripping formaldehyde, the reaction kettle is switched to a distillation state for dehydration.
8. A thermoplastic phenolic resin, which is characterized by being prepared by the preparation process of the thermoplastic phenolic resin as claimed in any one of claims 1 to 7.
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| CN202210613794.3A CN114874405A (en) | 2022-05-31 | 2022-05-31 | Thermoplastic phenolic resin and preparation process thereof |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005200489A (en) * | 2004-01-14 | 2005-07-28 | Sumitomo Bakelite Co Ltd | Manufacturing method of thermoplastic resin-modified novolak-type phenolic resin |
| CN103329042A (en) * | 2011-02-25 | 2013-09-25 | 住友电木株式会社 | Photoresist resin composition |
| CN103389622A (en) * | 2012-05-11 | 2013-11-13 | 住友电木株式会社 | Photoresist resin composition, photoresist and method for manufacturing liquid equipment |
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- 2022-05-31 CN CN202210613794.3A patent/CN114874405A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005200489A (en) * | 2004-01-14 | 2005-07-28 | Sumitomo Bakelite Co Ltd | Manufacturing method of thermoplastic resin-modified novolak-type phenolic resin |
| CN103329042A (en) * | 2011-02-25 | 2013-09-25 | 住友电木株式会社 | Photoresist resin composition |
| CN103389622A (en) * | 2012-05-11 | 2013-11-13 | 住友电木株式会社 | Photoresist resin composition, photoresist and method for manufacturing liquid equipment |
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