PRECISION CASTING WAX BASED ON GRAPHITE OXIDE MODIFIED ROSIN AND PRODUCTION METHOD THEREOF

Abstract

Disclosed are a precision casting wax based on graphite oxide modified rosin and its production method. The precision casting wax is composed of 20%30% of modified rosin, 50%65% of paraffin, 5%10% of an adhesion agent, 5%40% of PE wax, and 0%3% of montan wax (in mass percentage), and the total content adds up to 100%. The modified rosin is composed of first-grade rosin, graphite oxide, zinc oxide and pentaerythritol. The graphite oxide, zinc oxide, and pentaerythritol have a mass equal to 5%8%, 0.3%0.5%, and 5%8% of the mass of the first-grade rosin respectively. The modified rosin has a softening point of 98 C.103 C. and an acidity value of 15 KOH/g25 KOH/g. The present invention has the features of small needle penetration, small linear shrinkage rate, large bending strength, and small ash content, and thus can satisfy the requirements of high size precision and high surface quality of the precision casting.

Claims

1. A precision casting wax based on graphite oxide modified rosin, comprising the following components in percentage by mass: 20%30% of modified rosin, 50%65% of paraffin, 5%10% of an adhesion agent, 5%10% of PE wax, and 0%3% of montan wax, wherein the total content of the components is 100%.

2. The precision casting wax based on graphite oxide modified rosin according to claim 1, wherein the components of the modified rosin are first-grade rosin, graphite oxide, zinc oxide and pentaerythritol; the mass of the graphite oxide is equal to 5%8% of the mass of the first-grade rosin; the mass of the zinc oxide is equal to 0.3%0.5% of the mass of the first-grade rosin; the mass of the pentaerythritol is equal to 5%8% of the mass of the first-grade rosin; and the modified rosin has a softening point of 98 C.103 C. and an acidity value of 15 KOH/g25 KOH/g.

3. The precision casting wax based on graphite oxide modified rosin according to claim 1, wherein the paraffin is one or more selected from the group consisting of 58#, 62#, 64#, 66#, 68#, and 70# fully-refined or semi-refined waxes.

4. The precision casting wax based on graphite oxide modified rosin according to claim 1, wherein the adhesion agent is one or more selected from the group consisting of terpene resin, C5 petroleum resin, hydrogenated C5 petroleum resin and hydrogenated rosin.

5. The precision casting wax based on graphite oxide modified rosin according to claim 1, wherein the PE wax has a melting point of 100120 C.

6. The precision casting wax based on graphite oxide modified rosin according to claim 1, wherein the montan wax has a melting point of 75 C.90 C.

7. A production method of a precision casting wax based on graphite oxide modified rosin, comprising: 1) preparing a modified rosin; 2) obtaining 20%30% of the modified rosin, adding 5%10% of an adhesion agent, 5%1.0% of PE wax, and 0%3% of montan wax into the modified rosin, heating and blending the mixture until the mixture is melted completely to obtain a mixed solution A; 3) adding 50%65% of paraffin into the melted mixed solution A, and heating and blending the resulted mixture until it is melted completely to obtain a mixed solution B; 4) cooling the melted mixed solution B to produce particles to obtain the precision casting wax based on graphite oxide modified rosin.

8. The production method of the precision casting wax based on graphite oxide modified rosin according to claim 7, wherein preparing the modified rosin of Step 1).sub. comprises: providing a first-grade rosin, dissolving the first-grade rosin at 120 C. to obtain a first-grade rosin solution, and then adding graphite oxide, in an amount of 5%8% by weight of the first-grade rosin, zinc oxide, in an amount of 0.3%0.5% by weight of the first-grade rosin, and pentaerythritol, in an amount of 5%8% by weight of the first-grade rosin, sequentially into the first-grade rosin solution to obtain a mixed solution, and heating the mixed solution to 250 C.290 C., and blending the mixed solution until the mixed solution is in a molten state, so as to obtain a modified resin with a softening point of 98 C.103 C., and an acidity value of 15 KOH/g25 KOH/g.

9. The production method of the precision casting wax based on graphite oxide modified rosin according to claim 7, wherein the system temperature of Step 2) is 120 C.160 C.

10. The production method of the precision casting wax based on graphite oxide modified rosin according to claim 7, wherein the system temperature of Step 3) is 90 C.110 C.

Description

DESCRIPTION OF SPECIFIC EMBODIMENTS

[0027] The present invention is further elaborated by specific embodiments as follows:

Embodiment 1

[0028] 100 g of first-grade rosin (Jiangxi Masson Pine, softening point 82 C.) was added into a 1-liter high pressure reaction kettle and dissolved at 120 C., and 5 g of catalytic graphite oxide (equal to 5% of the mass of rosin) (Hubei Yihua Chemical Industry Co., Ltd.), 3 g of co-catalytic zinc oxide (equal to 0.3% of the mass of rosin) (Nanhua brand), and 5 g of pentaerythritol (equal to 5% of the mass of rosin) (Hubei Yihua Chemical Industry Co., Ltd.) were added, blended, and melted. The kettle was sealed and heated up to 280 C., and the system temperature was controlled to be not over 290 C., and the aforementioned chemical substances reacted for 3 hours. It was not necessary to separate the co-catalytic zinc oxide and catalytic graphite oxide from the remained pentaerythritol in the system to obtain a modified rosin resin mixture. The air in the kettle was s discharged and the pressure was released to drop the system temperature to approximately 140 C., and 40 g (8%) of C5 petroleum resin (YH-1288, Henghe Materials & Science Technology Co., Ltd.), 25 g (5%) of PE wax (SCG Chemicals, Thailand/LP0500F polyethylene wax, 115 C.) and 10 g (2%) of montan wax (Shangcheng brand, Yunnan) were added and completely melted, and then the mixture was further stirred for 30 minutes to drop the system temperature to approximately 100 C. 312 g (62.4%) of 58# semi-refined paraffin (Maoming Petrochemical, Nanhai brand) was added, heated, blended and melted, and then the mixture was further blended for 30 minutes, and finally cooled to form particles, so as to obtain the precision casting wax of the present invention.

[0029] Control Group 1: 113 g of unmodified rosin (with other conditions same as those of Embodiment 1) was added into a 1-liter high pressure reaction kettle and melted at 140 C., and 40 g (8%) of C5 petroleum resin, 25 g (5%) of PE wax, and 10 g (2%) of montan wax were added and completely melted, and further stirred for 30 minutes to drop the system temperature to approximately 100 C., and 312 g (62.4%) of paraffin was added, heated, blended and melted, and the mixture was further stirred for 30 minutes and cooled to form particles, so as to obtain the precision casting wax.

Embodiment 2

[0030] 100 g of first-grade rosin (Jiangxi Masson Pine, softening point 82 C.) was added into a 1-liter high pressure reaction kettle and dissolved at 120 C., and 8 g of catalytic graphite oxide (equal to 5% of the mass of rosin) (Hubei Yihua Chemical Industry Co., Ltd.), 3 g of co-catalytic zinc oxide (equal to 0.3% of the mass of rosin) (Nanhua brand), 5 g of pentaerythritol (equal to 5% of the mass of rosin) (Hubei Yihua Chemical Industry Co., Ltd.) were added, blended, and melted. The kettle was sealed and heated up to 280 C., and the system temperature was controlled to a temperature not over 290 C., and the aforementioned chemical substances were reacted for 3 hours, and it was not necessary to separate the co-catalytic zinc oxide and the catalytic graphite oxide from the remained pentaerythritol in the system to obtain a modified rosin resin mixture, and then the air in the kettle was discharged and released to drop the system temperature to approximately 140 C., and 40 g (8%) of terpene resin (T100, Shenzhen Jitian Chemical Co., Ltd.), 25 g (5%) of PE wax (SCG Chemicals, Thailand/LP0500F polyethylene wax, 115 C.) and 10 g (2%) of montan wax (Shangcheng brand, Yunnan) were added and melted completely, and then the mixture was further stirred for 30 minutes to drop the system temperature to approximately 100 C., and 309 g (62.4%) of 62# fully refined paraffin (Maorning Petroleum. Co., Ltd., Nanhai brand) was added, heated, blended and melted, and then further blended for 30 minutes, and finally cooled to form particles, so as to obtain the precision casting wax.

[0031] Control Group 2: 116 g of unmodified rosin (with other conditions same as those of Embodiment 2) was added into a 1-liter high pressure reaction kettle and melted at 140 C., and 40 g (8%) of C5 petroleum resin, 25 g (5%) of PE wax, and 10 g (2%) of montan wax were added and completely melted, and further stirred for 30 minutes to drop the system temperature to approximately 100 C., and 312 g (62.4%) of paraffin was added, heated, blended and melted, and the mixture was further stirred for 30 minutes and cooled to form particles, so as to obtain the precision casting wax.

Embodiment 3

[0032] 125 g of first-grade rosin (Jiangxi Masson Pine, softening point 82 C.) was added into a 1-liter high pressure reaction kettle and dissolved at 120 C., and 6.25 g of catalytic graphite oxide (equal to 5% of the mass of rosin) (Hubei Yihua Chemical. Industry Co., Ltd.), 3.75 g of co-catalytic zinc oxide (equal to 0.3% of the mass of rosin) (Nanhua brand), and 6.25 g of pentaerythritol (equal to 5% of the mass of rosin) (Hubei Yihua Chemical Industry Co., Ltd.) were added, blended, and melted. The kettle was sealed and heated up to 280 C., and the system temperature was controlled to a temperature not over 290 C., and the aforementioned chemical substances were reacted for 3 hours, and it was not necessary to separate the catalytic zinc oxide and graphite oxide from the remained pentaerythritol in the system to obtain a modified rosin resin mixture, and then the air in the kettle was discharged and released to drop the system temperature to approximately 140 C., 40 g (8%) of terpene resin (T100, Shenzhen Jitian Chemical Co., Ltd.), 25 g (7%) of PE wax (SCG Chemicals, Thailand/LP0500F polyethylene wax, 115 C.) and 10 g (2%) of montan wax (Shangcheng brand, Yunnan) were added and melted completely, and then the mixture was further stirred for 30 minutes to drop the system temperature to approximately 100 C. 283.75 g (62.4%) of 62# fully refined paraffin (Maoming Petroleum Co., Ltd., Nanhai brand) was heated, blended and melted, and the mixture was further blended for 30 minutes and cooled to form particles, so as to obtain the precision casting wax.

[0033] Control Group 3: 141.25 g of unmodified rosin (with other conditions same as those of Embodiment 3) was added into a 1liter high pressure reaction kettle and melted at 140 C., and 40 g (8%) of CS petroleum resin, 25 g (5%) of PE wax, and 10 g (2%) of montan wax were added and completely melted, and the mixture was further stirred for 30 minutes to drop the system temperature to approximately 100 C., and 283.75 g (62,4%) of paraffin was added, heated, blended and melted, and the mixture was further stirred for 30 minutes and cooled to form particles, so as to obtain the precision casting wax.

[0034] Performance Tests: The samples of precision casting wax of Embodiment 1, Embodiment 2, Embodiment 3, Control Group 1, Control Group 2 and Control Group 3 were measured and tested in the related material laboratory of Dongguan University of Technology, and the softening point, needle penetration, linear shrinkage rate, bending strength, viscosity and acidity value of each precision casting wax were measured and tested, and the experiment results are listed in Table 1 as follows:

[0035] Softening point: GB/T4507-84

[0036] Needle penetration: GB/T14235.5-93

[0037] Linear shrinkage rate: GB/T14235.4-93

[0038] Bending strength: GB/T14235.2-93

[0039] Ash content: GB/T14235.3-93

[0040] Viscosity: GB/T 14235.8-1993

[0041] Acidity value: GB/T 14235.6-1993

TABLE-US-00001 TABLE 1 Statistic Table of Experiment Results Softening Point (Ring Needle Acidity and Ball Penetration Linear Bending Ash Value Method (25 C. Shrinkage Strength Content Viscosity (mg Item C.) 0.1 mm) Rate (%) (MPa) (%) (mm2/120 C.) KOH/g) Embodiment 73.2 5.2 0.52 14 <0.02 67 6 1 Control 70.1 7.0 0.73 11 <0.02 82 16 Group 1 Embodiment 75.8 4.5 0.53 16 <0.02 69 6 2 Control 72.6 6.3 0.78 12 <0.02 81 17 Group 2 Embodiment 76.7 4.2 0.43 17 <0.02 76 6.8 3 Control 73.1 6.1 0.81 12 <0.02 93 18.4 Group 3

Analysis of the Results:

[0042] From the statistics table of experiment results (Table 1), after the rosin was modified, various different parameters of the precision casting wax were affected significantly, and the softening point of the precision casting wax of the present invention can be adjusted according to the selected materials to meet the requirements of smaller needle penetration, smaller linear shrinkage rate, larger bending strength, and smaller ash content and the invention further satisfied the requirements of high size precision and high surface quality of the precision casting. In summation, the precision casting wax of the present invention had good data and met the requirements of its practical production.

[0043] The embodiments described above are merely illustrative of several embodiments of the invention and are more specific and detailed. These are not to be construed as limiting the scope of the invention. While the invention has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those Skilled in the art without departing from the scope and spirit of the invention set forth in the claims.