A preparation process for polymerized rosin-modified phenolic resin

Abstract

This invention relates to the field of phenolic resin technology, specifically to a preparation process for polymerized rosin-modified phenolic resin. First, polymeric rosin with high dimer content is purified by devolatilization, adsorption decolorization, and antisolvent precipitation to obtain directionally polymerized rosin A. Then, an epoxidation reaction is performed to obtain epoxidized product B. Subsequently, cashew phenol, 3-pentadecanylphenol, and oleic acid are grafted in stages to obtain directionally modified polymeric rosin C. Simultaneously, a phenolic prepolymer is prepared. Finally, the prepolymer, modified rosin C, and natural rosin are polycondensed together, and an antioxidant is added to obtain the finished product. This process, through directional control of raw materials and staged reaction control, enables the resin to possess high softening point, light color stability, high n-heptane tolerance, and excellent processing safety, significantly improving batch consistency and making it suitable for high-performance ink binders.

Description

Technical Field

[0001] This invention relates to the field of phenolic resin technology, and more particularly to a preparation process for polymerized rosin-modified phenolic resin. Background Technology

[0002] Rosin-modified phenolic resin, as a key component of ink binders, directly affects the gloss, adhesion, and durability of printed materials. Traditional processes typically involve the direct condensation of rosin or ordinary polymerized rosin with phenols and formaldehyde, optimizing parameters such as softening point and viscosity by adjusting catalyst type, phenol-formaldehyde ratio, or condensation temperature. However, polymerized rosin itself suffers from significant compositional fluctuations, particularly in dimer content and color parameters, which are significantly influenced by raw material source and storage conditions. This makes it difficult to control the molecular weight distribution during resin synthesis, thus affecting batch-to-batch consistency.

[0003] While existing technologies attempt to compensate for raw material fluctuations by increasing polycondensation temperature or extending reaction time, this often leads to localized overheating or excessive polycondensation, exacerbating color deepening and acid value increases. Furthermore, the high-viscosity stage is prone to gelation or bubble accumulation due to residual small molecules or unreacted active components, posing safety hazards in production. Some improved processes introduce post-treatment refining or additive formulation, but these still fail to establish a structured control chain from the raw material pretreatment stage, only addressing single performance indicators and failing to simultaneously achieve synergistic improvements in multiple objectives such as high softening point, high solubility, and light color. Summary of the Invention

[0004] In view of this, the purpose of this invention is to propose a preparation process for polymerized rosin-modified phenolic resin, so as to achieve the resin with high softening point, high viscosity, low acid value, high n-heptane tolerance and light color stability under the condition that the composition of polymerized rosin fluctuates significantly and high viscosity condensation is prone to gelation / foaming, by directional regulation of raw materials and segmented reaction control, and significantly improve batch consistency and industrialization safety.

[0005] To achieve the above objectives, the present invention provides a preparation process for polymerized rosin-modified phenolic resin, comprising the following steps: (1) Polymerized rosin with a dimer content of more than 60% was devolatilized under reduced pressure to obtain pretreated polymerized rosin; (2) Dissolve the pretreated polymerized rosin in xylene, add activated clay for adsorption and decolorization, then add powdered activated carbon for adsorption and decolorization, and filter while hot to obtain a decolorized and clear solution; after cooling, add n-heptane as a reverse solvent to precipitate the dark-colored polymer group and filter to remove the precipitate; remove the solvent to obtain directional polymerized rosin A; (3) Dissolve directionally polymerized rosin A in xylene, add formic acid and benzyltriethylammonium chloride, then add hydrogen peroxide aqueous solution to carry out epoxidation reaction. Control the reaction temperature not to exceed 55℃, and control the epoxy value to reach 180-220mmol / 100g. Add triethyl phosphite to terminate the reaction and separate the aqueous phase. Deviation yields epoxidized directionally polymerized rosin B. (4) Under the catalysis of triphenylphosphine, cashew phenol, 3-pentadecanylphenol and oleic acid were sequentially subjected to ring-opening grafting reaction with epoxidized directional polymerized rosin B, and the process control was the decrease of epoxy value. Xylene was removed to obtain directional modified polymerized rosin C. (5) Phenol, p-tert-butylphenol and cashew phenol are dissolved in xylene, formic acid is added as a volatile acid catalyst, and then formaldehyde aqueous solution is added for methyl alcoholysis and initial condensation. After azeotropic dehydration and devolatation treatment, phenolic prepolymer is obtained. (6) Phenolic prepolymer, directional modified polymeric rosin C and natural resin rosin are mixed and then methanesulfonic acid is added as an accelerator to carry out the polycondensation reaction. After the reaction is completed, the vacuum is released and the temperature is lowered to 165-180℃. Antioxidant 1010 and antioxidant 168 are added and then filtered and cooled to obtain polymeric rosin modified phenolic resin.

[0006] Preferably, in step (1), after the polymerized rosin is stirred and melted at 200 r / min at 120℃ for 30 min, a sample is taken, and the dimer content is quantified by high performance liquid chromatography. The dimer content is greater than 60% as the threshold for entering the reactor, and the sample is de-volatile at 110℃ and 50 kPa for 30 min.

[0007] Preferably, in step (2), based on 1000 parts by weight of the pretreated polymerized rosin, xylene is 600 parts by weight, activated clay is 10-30 parts by weight, powdered activated carbon is 3-8 parts by weight, and n-heptane is 350-550 parts by weight.

[0008] Preferably, in step (3), based on 900 parts by mass of the directionally polymerized rosin A, xylene is 400 parts by mass, formic acid is 60 parts by mass, benzyltriethylammonium chloride is 5 parts by mass, hydrogen peroxide aqueous solution is 350 parts by mass and the mass fraction of the hydrogen peroxide aqueous solution is 30%, and triethyl phosphite is 6-15 parts by mass.

[0009] Preferably, in step (4), based on 930 parts by mass of the epoxidized directionally polymerized rosin B, xylene is 80 parts by mass, cashew phenol is 90-150 parts by mass, 3-pentadecanylphenol is 60-120 parts by mass, and oleic acid is 120-200 parts by mass.

[0010] Preferably, in step (4), cashew phenol is added at 120°C to react with triphenylphosphine and the epoxy value is controlled to decrease from 200 mmol / 100g to 120 mmol / 100g. Then, 3-pentadecanylphenol is added at 130°C to react with triphenylphosphine and the epoxy value is controlled to decrease from 120 mmol / 100g to 60 mmol / 100g. Then, oleic acid is added at 150°C to react with triphenylphosphine and the epoxy value is controlled to decrease from 60 mmol / 100g to 20 mmol / 100g. Finally, xylene is removed at 160°C and 20 kPa for 60 min.

[0011] Preferably, in step (5), xylene is 100 parts by mass, phenol is 160-220 parts by mass, p-tert-butylphenol is 120-180 parts by mass, cashew phenol is 140-200 parts by mass, formic acid is 6-12 parts by mass, and formaldehyde aqueous solution is 240-300 parts by mass, and the mass fraction of the formaldehyde aqueous solution is 37%.

[0012] Preferably, in step (6), the phenolic prepolymer is 550 parts by mass, the directionally modified polymerized rosin C is 1200 parts by mass, the natural resin rosin is 350 parts by mass, the methanesulfonic acid is 2-5 parts by mass, the antioxidant 1010 is 2 parts by mass, and the antioxidant 168 is 2 parts by mass.

[0013] Preferably, in step (6), the polycondensation reaction is carried out by heating to 215-230°C under nitrogen protection and switching to 18-25 kPa vacuum, maintaining the reaction at 215-230°C for 5-8 hours.

[0014] The beneficial effects of this invention are: This invention significantly improves the color stability of polymerized rosin through pretreatment and directional modification. Activated clay and powdered activated carbon are used to adsorb and decolorize the molten polymerized rosin, and n-heptane is used as an antisolvent to selectively precipitate the dark-colored polymer components. This effectively removes pigment precursors and thermally unstable impurities from the raw materials, reduces the tendency for chromophore formation during subsequent high-temperature polycondensation, and significantly improves the color of the finished resin with reduced batch-to-batch variations.

[0015] In the epoxidation reaction, the process safety of the high-temperature reaction was enhanced by controlling the epoxy value endpoint and using triethyl phosphite to terminate residual oxidizing substances. This step not only avoided side reactions caused by residual hydrogen peroxide but also effectively suppressed local crosslinking and bubble generation, resulting in better thermal stability and a wider processing window for the resin during subsequent high-temperature condensation.

[0016] By introducing cashew phenol, 3-pentadecanylphenol, and oleic acid in stages to perform time-controlled ring-opening grafting of epoxidized polymerized rosin, an ordered molecular structure was constructed. The progressively introduced aromatic segments and long-chain alkyl structures synergistically modulate the polarity and flexibility of the resin, giving it both high compatibility and film-forming strength in toluene and petroleum solvent systems. This results in excellent viscosity balance and abrasion resistance in printing binder applications.

[0017] The process design, which combines volatile acid catalysts with low-temperature antioxidants, further ensures the balance of the resin's final performance. The phenolic pre-condensation stage employs azeotropic dehydration to remove volatile components, reducing the impact of residual acid catalysts on color and acid value. Furthermore, the low-temperature addition of antioxidants 1010 and 168 in the post-condensation stage effectively avoids performance degradation caused by high-temperature degradation, ensuring stable resin performance during storage and use. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. Raw material parameters: the acid value of polymerized rosin is 145 mg KOH / g, the softening point is 115℃, and the color is ≤10; the acid value of natural resin rosin is 170 mg KOH / g, the softening point is 78℃, and the color is ≤WG grade; the activated clay is of the decolorizing grade; the powdered activated carbon is of the decolorizing grade.

[0019] Example 1: Step S1: Place the polymerized rosin into a reaction vessel, stir at 120℃ for 200 r / min to melt for 30 min, and then take a sample. Quantify the dimer content using high performance liquid chromatography (with a dimer content >60% as the entry threshold, and record the batch dimer content), and record the color using Gardner colorimetry. Subsequently, devolve at 110℃ and 50 kPa for 30 min to obtain pretreated polymerized rosin. Step S2: Add 600g xylene to the reactor and heat to 90℃. Add 1000g of pretreated polymerized rosin while stirring at 250r / min until completely dissolved. Then add 20g activated clay at 90℃ and stir for 40min. Add 5g powdered activated carbon and stir for 20min. Filter the solution while hot through a 200-mesh filter cloth to obtain a decolorized and clear solution. Cool the solution to 60℃ and maintain stirring at 200r / min. Slowly add 450g n-heptane as a countersolvent in batches over 60min. Continue to keep the solution at 60℃ for 60min and let it stand for 30min to allow the dark-colored polymer components to precipitate preferentially. Filter the solution again through a 200-mesh filter cloth to remove the precipitates. Remove the solvent from the filtrate at 90℃ and 50kPa for 60min, and then remove the residual solvent at 160℃ and 20kPa for another 60min to obtain directional polymerized rosin A. Step S3: Add 400g xylene to the reactor and heat to 50℃. Add 900g of directionally polymerized rosin A while stirring at 300r / min to homogenize it. Then add 60g formic acid and 5g benzyltriethylammonium chloride, maintain the reactor temperature at 45℃ to 55℃ and turn on the external circulation cooling. Add 350g of hydrogen peroxide aqueous solution (mass fraction 30%) in 7 portions (50g each time, 20min interval between each addition), and control the reactor temperature to not exceed 55℃ throughout the process. After the addition is completed, continue the reaction at 50℃ for 3h. Take a sample to test the epoxy value. When the epoxy value reaches 200mmol / 100g, add 10g of triethyl phosphite and stir for 30min to consume the residual hydrogen peroxide and peracid. Let it stand for 20min to separate the lower aqueous phase and discharge it. Deviation of the organic phase is carried out at 90℃ and 50kPa for 60min, and then at 130℃ and 20kPa for 60min to obtain epoxidized directionally polymerized rosin B. Step S4: Add 80g of xylene to the reactor and heat to 120℃. While stirring at 200r / min, add 930g of epoxidized directionally polymerized rosin B to form a homogeneous melt. Then add 120g of cashew phenol and 3g of triphenylphosphine, reacting at 120℃. Using the decrease in epoxy value as a process control indicator, reduce the epoxy value from 200mmol / 100g to 120mmol / 100g before adding 80g of xylene. 3-Pentadecylphenol and 2g of triphenylphosphine were reacted at 130°C to further reduce the epoxy value from 120mmol / 100g to 60mmol / 100g. Then, 160g of oleic acid and 2g of triphenylphosphine were added, and the temperature was raised to 150°C to further reduce the epoxy value from 60mmol / 100g to 20mmol / 100g. Subsequently, xylene was removed at 160°C and 20kPa for 60min to obtain directionally modified polymerized rosin C. Step S5: Add 180g phenol, 160g p-tert-butylphenol, 160g cashew phenol and 100g xylene to the reactor. Stir at 70℃ for 300r / min to mix completely, then add 8g formic acid as a volatile acid catalyst. Then slowly add 250g formaldehyde aqueous solution (mass fraction 37%) over 60min, while simultaneously raising the reactor temperature to 90℃ and holding for 2h to complete methyl alcoholization and initial condensation. After that, raise the temperature to 105℃ for azeotropic dehydration, and continue reflux to separate water until the amount of water separated basically no longer increases. Then remove xylene and residual volatile catalyst at 120℃ and 30kPa for 60min to obtain phenolic prepolymer. Step S6: Add 550g of phenolic prepolymer, 1200g of directionally modified polymeric rosin C, and 350g of natural resin rosin to a reactor. Stir at 130°C for 200r / min until completely melted and homogeneous. Then add 3g of methanesulfonic acid as a promoter. Subsequently, raise the reactor temperature to 180°C and hold for 1 hour. Then, under nitrogen protection, raise the reactor temperature to 220°C and switch to a 20kPa vacuum. Maintain the reaction at 220°C for 6 hours. After the reaction is completed, first release the vacuum and cool down to 180°C. Then add 2g of antioxidant 1010 and 2g of antioxidant 168 and stir for 20 minutes to fully dissolve. Then, filter the mixture while hot through a 200-mesh metal filter and discharge and cool to obtain polymeric rosin-modified phenolic resin. Example 2: Based on Example 1, the amounts of key raw materials were optimized as follows: in step S2, the amount of activated clay was 30g, the amount of powdered activated carbon was 8g, and the amount of n-heptane was 500g; in step S4, the amount of cashew phenol was 110g, the amount of 3-pentadecanylphenol was 90g, and the amount of oleic acid was 150g; in step S5, the amount of phenol was 160g, the amount of p-tert-butylphenol was 180g, the amount of cashew phenol was 140g, and the amount of formaldehyde aqueous solution was 240g; the remaining conditions were the same as in Example 1.

[0020] Example 3: Based on Example 1, the dosage of key raw materials and final polycondensation conditions were optimized as follows: In step S2, the amount of activated clay was 15g, the amount of powdered activated carbon was 3g, and the amount of n-heptane was 400g; in step S3, 12g of triethyl phosphite was added when the epoxy value reached 190mmol / 100g; in step S4, the amount of cashew phenol was 130g, the amount of 3-pentadecanylphenol was 110g, and the amount of oleic acid was 130g; in step S5, the amount of phenol was 200g, the amount of p-tert-butylphenol was 150g, the amount of cashew phenol was 170g, the amount of formic acid was 10g, and the amount of formaldehyde aqueous solution was 270g; in step S6, the amount of methanesulfonic acid was 4g, and the reactor temperature was raised to 225℃ under nitrogen protection and switched to 18kPa vacuum, and the reaction was maintained at 225℃ for 7h; the remaining conditions were the same as in Example 1.

[0021] Example 4: Based on Example 1, the dosage of key raw materials and final polycondensation conditions were optimized as follows: In step S2, the amount of activated clay was 25g, the amount of powdered activated carbon was 6g, and the amount of n-heptane was 550g; in step S3, 8g of triethyl phosphite was added when the epoxy value reached 210mmol / 100g; in step S4, the amount of cashew phenol was 100g, the amount of 3-pentadecanylphenol was 70g, and the amount of oleic acid was 200g; in step S5, the amount of p-tert-butylphenol was 140g, the amount of cashew phenol was 200g, the amount of formic acid was 6g, and the amount of formaldehyde aqueous solution was 260g; in step S6, the reactor temperature was raised to 218℃ under nitrogen protection and switched to 22kPa vacuum, and the reaction was maintained at 218℃ for 6h; the remaining conditions were the same as in Example 1.

[0022] Example 5: Based on Example 1, the epoxy termination point, phenol addition, and antioxidant system addition conditions were optimized as follows: In step S3, 15g of triethyl phosphite was added when the epoxy value reached 180mmol / 100g; in step S4, cashew phenol was 150g, 3-pentadecanylphenol was 60g, and oleic acid was 150g; in step S5, formic acid was 12g; in step S6, methanesulfonic acid was 2g, and the reactor temperature was raised to 230℃ under nitrogen protection and switched to 20kPa vacuum, maintaining the reaction at 230℃ for 5h; after the reaction, the vacuum was first released and the temperature was lowered to 175℃, and then 3g of antioxidant 1010 and 3g of antioxidant 168 were added and stirred for 20min; the remaining conditions were the same as in Example 1.

[0023] Example 6: Based on Example 1, the dosage of key raw materials and final polycondensation conditions were optimized as follows: In step S2, the amount of activated clay was 10g, the amount of powdered activated carbon was 4g, and the amount of n-heptane was 350g; in step S3, when the epoxy value reached 220mmol / 100g, 6g of triethyl phosphite was added; in step S4, the amount of cashew phenol was 90g, the amount of 3-pentadecanylphenol was 120g, and the amount of oleic acid was 120g; in step S5, the amount of phenol was 220g, the amount of p-tert-butylphenol was 120g, the amount of cashew phenol was 160g, and the amount of formaldehyde aqueous solution was 300g; in step S6, the amount of methanesulfonic acid was 5g, and the reactor temperature was raised to 215℃ under nitrogen protection and switched to 25kPa vacuum, and the reaction was maintained at 215℃ for 8h; after the reaction was completed, the vacuum was first released and the temperature was lowered to 165℃, and then 1g of antioxidant 1010 and 1g of antioxidant 168 were added and stirred for 20min; the remaining conditions were the same as in Example 1.

[0024] Comparative Example 1: The difference from Example 1 is that the dimer content of the polymerized rosin in step S1 is 45%, and the dimer content >60% is not used as the threshold for entering the reactor; the other conditions are the same as in Example 1.

[0025] Comparative Example 2: The difference from Example 1 is that: no activated clay and powdered activated carbon are added in step S2, and the polymerized rosin is directly filtered through a 200-mesh filter cloth while hot after being completely dissolved in xylene; the other conditions are the same as in Example 1.

[0026] Comparative Example 3: The difference from Example 1 is that in step S2, after obtaining the decolorized and clear solution, n-heptane is not added as an antisolvent, and the dark color component is not separated by filtration; the other conditions are the same as in Example 1.

[0027] Comparative Example 4: The difference from Example 1 is that in step S3, 10g of triethyl phosphite is added when the epoxy value reaches 260mmol / 100g; the other conditions are the same as in Example 1.

[0028] Comparative Example 5: The difference from Example 1 is that in step S3, triethyl phosphite is not added after the epoxy value reaches 200 mmol / 100g; the other conditions are the same as in Example 1.

[0029] Comparative Example 6: The difference from Example 1 is that in step S4, 120g of cashew phenol, 80g of 3-pentadecanylphenol, 160g of oleic acid and 7g of triphenylphosphine are added to the epoxidized directional polymerization rosin B at 120°C. Then, the reaction is carried out according to the temperature and time program of 120°C for 2h, 130°C for 2h and 150°C for 2h. The epoxy value is reduced from 200mmol / 100g to 20mmol / 100g as the process control index. The other conditions are the same as in Example 1.

[0030] Performance testing: The polymerized rosin-modified phenolic resins obtained in Examples 1-6 and Comparative Examples 1-6 were cooled, pulverized, and passed through a 60-mesh sieve. They were then vacuum-dried at 60°C and 20 kPa for 2 hours to remove volatiles and stored in a sealed, light-protected container. Samples for solution testing were prepared with a resin:toluene ratio of 50g:50g, stirred mechanically at 300 rpm for 30 minutes at 25°C, and allowed to stand for 30 minutes. The supernatant was then filtered through a 0.45 μm filter membrane as the test solution. The binder material for printing adhesion and film formation testing was prepared with a resin:linseed oil:petroleum solvent ratio of 55g:30g:15g. The resin and linseed oil were added to a reaction vessel, stirred at 180°C for 200 rpm to melt and homogenize for 30 minutes, then petroleum solvent was added. The mixture was stirred at 180°C for another 200 rpm for 30 minutes, then cooled to 25°C and allowed to stand for 24 hours to remove bubbles, yielding a standard binder material sample.

[0031] Gardner colorimetry: The determination shall be carried out in accordance with GB / T 22295-2008. Take the test solution of resin:toluene = 50g:50g, put it into a 10mm cuvette at 25℃, and perform transmission colorimetry with the standard color scale using a Gardner colorimeter tube. The Gardner color number that is closest to and not lighter than the sample color shall be taken as the result. Each sample shall be measured in parallel 3 times, and the arithmetic mean shall be taken and reported to 0.5.

[0032] Softening point (ring and ball method): The determination shall be carried out in accordance with GB / T 9284.1-2015. The dried resin sample shall be melted at 160℃ and poured into a metal ring for molding. After cooling to 25℃, the upper and lower surfaces shall be scraped flat with a blade. The steel ball shall be placed in the center of the sample and placed in the heating medium according to the standard device. The sample shall be heated at a heating rate of 5℃ / min. The temperature at which the steel ball causes the sample to fall to the specified contact position shall be recorded as the softening point. Each sample shall be measured twice in parallel, and the arithmetic mean shall be taken and reported to 0.1℃.

[0033] Acid value (total acid value): Determined according to Method B of GB / T 6743-2008. Weigh 1.000g of dried resin sample (accurate to 0.001g) into a 250mL Erlenmeyer flask, add 50mL of toluene / ethanol mixed solvent (volume ratio 2:1) to dissolve, add 0.5mL of phenolphthalein indicator (1% ethanol solution by mass), and titrate with 0.100mol / L potassium hydroxide ethanol standard titration solution until the solution turns pink and remains pink for 30s. Calculate the acid value based on the volume consumed and express it as mgKOH / g. Each sample is measured twice in parallel, and the arithmetic mean is taken and reported to 0.1mgKOH / g.

[0034] Solution viscosity (25℃, 50% toluene solution): determined according to GB / T 13217.4-2020. The supernatant of the filtered solution with resin:toluene = 50g:50g was used as the sample. After equilibration in a constant temperature water bath at 25℃ for 30min, the viscosity was measured at 25℃ using a rotational viscometer with a No. 4 rotor and a rotation speed of 60r / min. The viscosity value was recorded after the reading stabilized for 60s. Each sample was measured in parallel 3 times, and the arithmetic mean was taken and expressed in mPa·s.

[0035] n-Heptane tolerance (25℃): The turbidity endpoint determination principle in Appendix B of GB / T 24138-2009 was used to determine and fix the sample system. 50.0 g of resin and 50.0 g of toluene were weighed and added to a 250 mL jacketed beaker with a stirrer. The mixture was stirred at 300 r / min for 30 min in a constant temperature water bath at 25℃ to form a homogeneous solution. n-Heptane was added with a burette at a mass dropping rate of 10.0 g / min and stirring was continued. After turbidity appeared, n-Heptane was added dropwise for 30 s and then the addition was stopped. If the turbidity did not disappear after standing for 5 min after stopping, it was determined to be the endpoint. The cumulative mass of n-Heptane added at the endpoint was recorded as m (g). The n-Heptane tolerance T = m / 50.0 (expressed as g n-Heptane / g resin) was calculated. Each sample was measured twice in parallel, and the arithmetic mean was taken and reported to 0.01.

[0036] Gel time: The gel time was determined according to GB / T 33315-2016. 2.00 g of resin sample was placed in a standard test tube. The constant temperature oil bath temperature was set to 150℃ and the timing was started after the sample was completely melted. The sample was stirred uniformly with a glass rod at a frequency of 1 time / s, and the time when obvious stringing occurred and the flow could no longer continue was recorded as the gel time. Each sample was measured twice in parallel, and the arithmetic mean was taken and expressed in seconds.

[0037] Printing viscosity (binder viscosity tester method): The viscosity was determined according to GB / T 18723-2002. The above standard binder sample was taken and the viscosity was measured using a viscosity tester under constant temperature conditions of 32℃. The instrument speed was 800r / min. After pre-shearing for 60s, the viscosity value was read and recorded. Each sample was measured in parallel 3 times, and the arithmetic mean was taken and reported to 0.1 units.

[0038] Abrasion resistance: The test ink was prepared according to GB / T 7706-2008. The standard binder and carbon black pigment were ground at a mass ratio of 70:30 on a three-roll mill until the fineness was ≤10μm. The ink film was prepared on coated paper using a laboratory ink leveling rod with a wet film thickness of 12μm. After being placed at 25℃ and 50% relative humidity for 24h, the abrasion resistance test was conducted. The abrasion resistance test load was 4.0N and the number of cycles was 100. The decrease in optical density of the ink film after abrasion was recorded as the result. Each sample was tested once and ΔD was recorded.

[0039] Table 1 Performance Test Results

[0040] Data Analysis: As can be seen from the data in Table 1, the polymerized rosin-modified phenolic resin prepared by this invention exhibits significant advantages in key indicators such as color, softening point, acid value, solution viscosity, and n-heptane tolerance. On the one hand, the adsorption and decolorization by activated clay and powdered activated carbon, combined with the selective precipitation of dark-colored polymer components by n-heptane antisolvent, allows the chromophores and abnormal polymer components at the raw material end to converge synchronously, thereby suppressing color fluctuations while maintaining the strength and solubility of the resin skeleton. On the other hand, by controlling the epoxy value endpoint and introducing triethyl phosphite after the hydrogen peroxide reaction to consume residual oxidizing substances, the tendency of local crosslinking induced by the subsequent high-temperature side reactions is reduced, keeping the gel time within a suitable window for processing and storage. Furthermore, the sequential ring-opening grafting of cashew phenol, 3-pentadecanylphenol, and oleic acid gradually establishes the distribution of polarity, flexibility, and hydrophobic segments in the system, promoting improved compatibility with toluene and petroleum solvent systems. Ultimately, in the application of binders, this results in a comprehensive balance of viscosity and abrasion resistance, demonstrating the comprehensive performance gains brought about by multi-step synergy.

[0041] As can be seen from the data in Example 1 and Comparative Example 1 in Table 1, when the polymerized rosin was not controlled by a dimer content threshold for batching into the reactor, the resin color, acid value, and n-heptane tolerance all deteriorated simultaneously, and the softening point and solution viscosity were difficult to control simultaneously within the same window. The main reason for this is that the resin acid composition in raw materials with low dimer content is more prone to fluctuation, resulting in a discrete distribution of the degree of polymerization and end-group residues.

[0042] As can be seen from the data in Table 1 for Example 1 and Comparative Examples 2 and 3, when the decolorization with activated clay and powdered activated carbon is omitted, or when the n-heptane antisolvent precipitation step is omitted, both the color and n-heptane tolerance decrease simultaneously, accompanied by a comprehensive degradation in solution viscosity and abrasion resistance. This is because adsorption decolorization primarily removes polar colorants and impurity precursors from catalytic side reactions, while antisolvent precipitation is more focused on eliminating dark-colored aggregates with higher molecular weights. Although they target different substances, they both determine the effective molecular groups that are "soluble, fluid, and capable of film formation." Retaining only one of them often only improves a single aspect and makes it difficult to simultaneously achieve color convergence and improved compatibility.

[0043] As can be seen from the data in Example 1 and Comparative Example 4 in Table 1, when the epoxy value control endpoint deviates and increases significantly, the softening point and solution viscosity increase, while the gel time shortens and the color tends to darken, and the tolerance to n-heptane is difficult to increase simultaneously. The main reason is that an excessive number of epoxy sites amplifies the local reaction density during subsequent ring-opening grafting and polycondensation processes, easily introducing a higher proportion of branched and locally cross-linked structures, thus creating a contradiction between high viscosity and a low processing window, and increasing the probability of chromophore formation by side reactions in the high-temperature stage. Therefore, more epoxy sites are not necessarily better; they must be matched with the subsequent progressive ring-opening rhythm to obtain a comprehensive performance that balances softening point, solubility, and safety.

[0044] As can be seen from the data in Table 1 for Example 1 and Comparative Example 5, when triethyl phosphite is not added after the hydrogen peroxide reaction, the gel time is significantly shortened and the color and abrasion resistance decrease simultaneously. The main reason for this is that residual hydrogen peroxide and peracid still possess oxidizing and initiating capabilities at high temperatures, easily inducing non-selective reactions of chain segments, forming local cross-links and chromophore regeneration, thereby exacerbating the processing instability and performance drift of the system. Therefore, the termination treatment with triethyl phosphite is not only a safe measure to remove residual oxides, but also achieves a synergistic gain in color stability and a wider processing window by suppressing subsequent side reactions.

[0045] As can be seen from the data in Example 1 and Comparative Example 6 in Table 1, when cashew phenol, 3-pentadecanylphenol, and oleic acid are added all at once in the same stage without segmented progressive control, the tolerance and abrasion resistance of n-heptane decrease, and the viscosity fluctuation increases. The main reason is that a single addition causes the ring-opening reactions of different functional groups to compete in time and space, easily resulting in uneven grafting density and local enrichment. This makes it difficult to gradually establish the polarity distribution and molecular weight configuration of the system as expected, thus weakening the synergistic effect of "solubilization-viscosity enhancement-film strength." In contrast, progressive grafting uses a segmented decrease in epoxy value as a process control signal, allowing hydrophobic and aromatic segments to be introduced sequentially and complete structural rearrangement. This makes it easier to form effective molecular groups that are both strong and compatible, demonstrating the synergy and unexpected comprehensive performance improvement brought about by the process sequence.

[0046] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity.

Claims

1. A preparation process for polymerized rosin-modified phenolic resin, characterized in that, Includes the following steps: (1) Polymerized rosin with a dimer content greater than 60% was devolatilized under reduced pressure to obtain pretreated polymerized rosin; (2) Dissolve the pretreated polymerized rosin in xylene, add activated clay for adsorption and decolorization, then add powdered activated carbon for adsorption and decolorization, and filter while hot to obtain a decolorized and clear solution; After cooling, n-heptane was added as a reverse solvent to precipitate the dark-colored polymer components, which were then filtered out. Solvent removal yielded directionally polymerized rosin A. (3) Dissolve directionally polymerized rosin A in xylene, add formic acid and benzyltriethylammonium chloride, then add hydrogen peroxide aqueous solution to carry out epoxidation reaction. Control the reaction temperature not to exceed 55℃, and control the epoxy value to reach 180-220mmol / 100g. Add triethyl phosphite to terminate the reaction and separate the aqueous phase. Deviation yields epoxidized directionally polymerized rosin B. (4) Under the catalysis of triphenylphosphine, cashew phenol, 3-pentadecanylphenol and oleic acid were sequentially subjected to ring-opening grafting reaction with epoxidized directional polymerized rosin B, and the process control was the decrease of epoxy value. Xylene was removed to obtain directional modified polymerized rosin C. (5) Phenol, p-tert-butylphenol and cashew phenol are dissolved in xylene, formic acid is added as a volatile acid catalyst, and then formaldehyde aqueous solution is added for methyl alcoholysis and initial condensation. After azeotropic dehydration and devolatation treatment, phenolic prepolymer is obtained. (6) Phenolic prepolymer, directional modified polymeric rosin C and natural resin rosin are mixed and then methanesulfonic acid is added as an accelerator to carry out the polycondensation reaction. After the reaction is completed, the vacuum is released and the temperature is lowered to 165-180℃. Antioxidant 1010 and antioxidant 168 are added and then filtered and cooled to obtain polymeric rosin modified phenolic resin.

2. The preparation process of the polymerized rosin-modified phenolic resin according to claim 1, characterized in that, In step (1), the polymerized rosin is stirred and melted at 200 r / min at 120℃ for 30 min, and then sampled. The content of dimer is quantified by high performance liquid chromatography. The dimer content is greater than 60% as the threshold for entering the reactor, and the product is de-volatile at 110℃ and 50 kPa for 30 min.

3. The preparation process of the polymerized rosin-modified phenolic resin according to claim 1, characterized in that, In step (2), based on 1000 parts by mass of the pretreated polymerized rosin, xylene is 600 parts by mass, activated clay is 10-30 parts by mass, powdered activated carbon is 3-8 parts by mass, and n-heptane is 350-550 parts by mass.

4. The preparation process of the polymerized rosin-modified phenolic resin according to claim 1, characterized in that, In step (3), based on 900 parts by mass of the directionally polymerized rosin A, xylene is 400 parts by mass, formic acid is 60 parts by mass, benzyltriethylammonium chloride is 5 parts by mass, hydrogen peroxide aqueous solution is 350 parts by mass and the mass fraction of the hydrogen peroxide aqueous solution is 30%, and triethyl phosphite is 6-15 parts by mass.

5. The preparation process of the polymerized rosin-modified phenolic resin according to claim 1, characterized in that, In step (4), based on 930 parts by mass of the epoxidized directionally polymerized rosin B, xylene is 80 parts by mass, cashew phenol is 90-150 parts by mass, 3-pentadecanophenol is 60-120 parts by mass, and oleic acid is 120-200 parts by mass.

6. The preparation process of the polymerized rosin-modified phenolic resin according to claim 1, characterized in that, In step (4), cashew phenol is added at 120°C to react with triphenylphosphine and the epoxy value is controlled to decrease from 200 mmol / 100g to 120 mmol / 100g. Then, 3-pentadecanylphenol is added at 130°C to react with triphenylphosphine and the epoxy value is controlled to decrease from 120 mmol / 100g to 60 mmol / 100g. Then, oleic acid is added at 150°C to react with triphenylphosphine and the epoxy value is controlled to decrease from 60 mmol / 100g to 20 mmol / 100g. Finally, xylene is removed at 160°C and 20 kPa for 60 min.

7. The preparation process of the polymerized rosin-modified phenolic resin according to claim 1, characterized in that, In step (5), xylene is 100 parts by mass, phenol is 160-220 parts by mass, p-tert-butylphenol is 120-180 parts by mass, cashew phenol is 140-200 parts by mass, formic acid is 6-12 parts by mass, and formaldehyde aqueous solution is 240-300 parts by mass, and the mass fraction of the formaldehyde aqueous solution is 37%.

8. The preparation process of the polymerized rosin-modified phenolic resin according to claim 1, characterized in that, In step (6), the phenolic prepolymer is 550 parts by mass, the directional modified polymerized rosin C is 1200 parts by mass, the natural resin rosin is 350 parts by mass, the methanesulfonic acid is 2-5 parts by mass, the antioxidant 1010 is 2 parts by mass, and the antioxidant 168 is 2 parts by mass.

9. The preparation process of the polymerized rosin-modified phenolic resin according to claim 1, characterized in that, In step (6), the polycondensation reaction is carried out by heating to 215-230℃ under nitrogen protection and switching to 18-25kPa vacuum, maintaining the reaction at 215-230℃ for 5-8 hours.

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