JP5807113B2 - Styrene-acrylonitrile resin having improved transparency and method for producing the same - Google Patents

Description

  The present disclosure relates generally to methods for producing, manufacturing or preparing styrene-acrylonitrile resins. More particularly, the present disclosure shows superior transparency, improved clarity, reduced coloration as a result of polymerization reactions that occur in the presence of appropriate amounts of 1,1-di (tert-butylperoxy) cyclohexane. Relates to a process for producing, manufacturing or preparing a styrene-acrylonitrile resin having a very low haze and / or a better physical appearance.

  Styrene acrylonitrile resin, commonly known as SAN resin or SAN, is a transparent copolymer thermoplastic. SANs are widely used in food containers, kitchenware, computer products, packaging materials such as cosmetic containers, battery cases, plastic optical fibers and electronics appliances. In addition, SAN is often used instead of polystyrene because of its greater heat resistance. SAN resins can also be used to produce or manufacture acrylonitrile butadiene styrene (ABS) with high chemical resistance, strength, toughness and stiffness.

  SANs are produced (produced, manufactured or prepared) by copolymerizing styrene and acrylonitrile monomers. Currently, there are several production methods or processes for producing SAN resins on an industrial scale; for example, emulsion polymerization, suspension polymerization, or continuous bulk polymerization. Continuous bulk polymerization processes or processes are often used because of the benefits that result from minimal or less impurities and less energy consumption or cost. During the polymerization process of styrene and acrylonitrile monomers, the monomers are heated to a high or relatively high temperature in order to generate free radicals and thereby initiate the polymerization reaction thermally. The reaction temperature must be kept high enough so as not to cause defects in the overall production process of the polymerization. However, at the process conditions or conditions, and more particularly at the high reaction temperatures required for the thermal initiation of the polymerization, production or manufacturing processes are undesirable, unacceptable and / or unavoidable. This produces a SAN resin product that is yellowish or has reduced transparency. This phenomenon is even more apparent when producing SAN resins with high acrylonitrile content to achieve higher or more durable mechanical properties due to the high reaction temperatures required. In such a situation, the entire SAN resin manufacturing process must be stopped, flushing out unwanted SAN resin, and restarted to produce and obtain a SAN resin with acceptable transparency. Such interruption of the process undesirably results in reduced process efficiency, longer manufacturing time required, and increased manufacturing costs.

  Therefore, for a method, process or technique for preparing, producing or manufacturing SAN resins with better, improved, improved or superior transparency without sacrificing overall process efficiency There is a need for. More specifically, there is an urgent need for methods, processes or techniques to produce SAN resins at lower temperatures (preparing, producing or manufacturing) to reduce undesirable yellowish SAN resins resulting from higher reaction temperatures. There is a need. Furthermore, there is a need for improved methods, processes or techniques for preparing, producing or manufacturing SAN resins having shorter process or production times and / or higher process yields.

  In accordance with one aspect of the disclosure, a method for producing a styrene acrylonitrile (SAN) resin with improved transparency comprises a certain amount (eg, mass or weight) of styrene monomer and acrylonitrile monomer under 1,1-di (tert -Butylperoxy) cyclohexane exposed to 1,1-di (tert-butylperoxy) cyclohexane has a concentration of about 5 to 500 million parts per million (ppm) based on the amount of styrene monomer and acrylonitrile monomer under consideration Initiating a polymerization reaction involving a styrene monomer and an acrylonitrile monomer exposed to 1,1-di (tert-butylperoxy) cyclohexane; continuing, maintaining or sustaining the polymerization reaction during the polymerization time; Including stopping; and obtaining a SAN resin having a haze value significantly lower than about 0.50 The Depending on the details of the embodiment, the SAN resin can have a haze value of about 0.45, 0.40, 0.35, 0.30, 0.25, 0.20, 0.15 or 0.10 or less.

  The method further includes exposing the styrene monomer and acrylonitrile monomer to the solvent; exposing the styrene monomer and acrylonitrile monomer to the chain transfer agent; and the styrene monomer and acrylonitrile monomer to the solvent, chain transfer agent and 1,1- Intimate blending with each of the di (tert-butylperoxy) cyclohexanes can be included.

  The initiation of the polymerization reaction involves exposing the styrene monomer and the acrylonitrile monomer to a temperature of about 85-130 ° C. (eg, about 90, 100, 110, 115, 120 or 125 ° C.) to produce 1,1-di (tert-butylperoxy ) In the presence of cyclohexane can be included to facilitate or enable the initiation of polymerization. The continuation, maintenance or continuation of the polymerization reaction is accomplished by exposing the styrene monomer and acrylonitrile monomer to a temperature of about 85-130 ° C. for a polymerization time interval of about 0.5-3.5 hours (eg, a time interval of about 1.0-3.0 hours) In the presence of 1-di (tert-butylperoxy) cyclohexane, to promote or sustain the polymerization.

  In some embodiments, exposing the styrene monomer and acrylonitrile monomer to 1,1-di (tert-butylperoxy) cyclohexane may be other than 1,1-di (tert-butylperoxy) cyclohexane to styrene monomer and acrylonitrile monomer. Occurs without exposure to other polymerization initiators. Another embodiment involves exposing styrene monomer and acrylonitrile monomer to a polymerization initiator other than 1,1-di (tert-butylperoxy) cyclohexane, wherein 1,1-di (tert-butylperoxy) The concentration of cyclohexane is at least about 80% greater (eg, about 90%, 95% or 98% greater) than the concentration of initiator other than 1,1-di (tert-butylperoxy) cyclohexane.

  Certain raw materials of improved transparency SAN resin produced according to embodiments of the present disclosure or chemical properties other than transparency or haze are produced in the absence of 1,1-di (tert-butylperoxy) cyclohexane. The corresponding properties of the SAN resin may be substantially the same. For example, the improved transparency SAN resin produced according to embodiments of the present disclosure is a melt flow index for a low transparency SAN resin produced in the absence of 1,1-di (tert-butylperoxy) cyclohexane. It can have substantially the same MFI and IV as (MFI) and intrinsic viscosity (IV).

  In accordance with another aspect of the present disclosure, a computer-based process that is executed on a computer and instructed to produce or manufacture styrene acrylonitrile (SAN) resin with improved transparency from styrene monomer and acrylonitrile monomer Determining a series of process parameters for producing a SAN resin to receive a target haze value in response to user input directed to a computer system; for the styrene monomer and acrylonitrile monomer under consideration; Determining the amount; and 1,1-di (tert-butylperoxy) cyclohexane suitable for producing SAN resins having a target haze value for the amount of styrene monomer and acrylonitrile monomer under consideration Including automatically determining the concentration

  Determining a series of process parameters includes receiving at least one target polymerization reaction temperature and a target polymerization time in response to user input directed to a computer system; and / or a target minimum And determining the actual or required polymerization time expected to correspond to the percent polymer conversion.

  The method further includes producing a SAN resin having a target haze value, wherein the production of such SAN resin comprises a determined amount of the styrene monomer and acrylonitrile monomer under consideration at a determined concentration. And combining with 1,1-di (tert-butylperoxy) cyclohexane. The determined 1,1-di (tert-butylperoxy) cyclohexane concentration can be about 5-500 ppm and the target haze value is significantly lower than about 0.5 (eg, the target haze value is about 0.45 , 0.40, 0.35, 0.30, 0.25, 0.20, 0.15 or 0.10 or less).

FIG. 1 shows improved or high transparency / reduced or low haze styrene using 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent in accordance with an embodiment of the present disclosure. 2 is a flowchart of a method for preparing, manufacturing or producing acrylonitrile (SAN) resin. FIG. 2A shows the total of styrene monomer and acrylonitrile monomer mixed or blended with or exposed to 1,1-di (tert-butylperoxy) cyclohexane for the percent conversion achieved for a polymerization time of 2 hours. 2 is a typical graph illustrating the relationship of ppm of 1,1-di (tert-butylperoxy) cyclohexane to weight. FIG. 2B shows the total of styrene and acrylonitrile monomers mixed or blended with or exposed to 1,1-di (tert-butylperoxy) cyclohexane versus percent conversion achieved for a 3 hour polymerization time. 3 is another exemplary graph illustrating the relationship of ppm of 1,1-di (tert-butylperoxy) cyclohexane to weight. FIG. 3 is a graph showing the SAN resin haze value measured relative to the total weight of styrene and acrylonitrile monomers mixed or blended with or exposed to 1,1-di (tert-butylperoxy) cyclohexane. 6 is a corresponding exemplary graph illustrating the ppm relationship of 1-di (tert-butylperoxy) cyclohexane. FIG. 4 shows improved or high transparency / reduced or low haze using 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent according to another embodiment of the present disclosure. 2 is a flow chart of a method for producing the SAN resin or composition.

  Embodiments of the present disclosure provide excellent, high, very high or essentially maximum transparency or equivalently, styrene acrylonitrile (equivalent to reduced, low, very low or essentially minimum haze value). SAN) relates to an embodiment of a method for producing a resin. The method according to the present disclosure provides suitable auxiliaries or sacrificial agents for styrene and acrylonitrile monomers that significantly lower the temperature at which polymerization occurs, significantly increase the polymerization reaction rate, and significantly increase the degree of monomer conversion to polymer. Or exposure to a quasi-catalyst. Embodiments of the present disclosure further relate to SAN resins produced by such methods, wherein the SAN resin has a low or very low haze value, such as less than about 0.50 or significantly lower than about 0.50 haze value, such as A haze value of less than about 0.50 and greater than or equal to about 0.10 (eg, a haze value of about 0.18-0.48, or a haze value of about 0.45, 0.40, 0.35, 0.30, 0.25, 0.20, 0.15, or 0.10 or less).

  In various embodiments, the auxiliary or sacrificial agent or quasi-catalyst is a specific organic peroxide, ie, 1,1-di (tert-butylperoxy) cyclohexane (hereinafter referred to as a sacrificial agent for brevity and clarity). Is or includes it. Establish, change, adjust, or customize the concentration of 1,1-di (tert-butylperoxy) cyclohexane to produce SAN resins with target or intended haze values as described in more detail below. can do.

Other organic peroxides such as benzoyl peroxide [C ₆ H ₅ C (O)] ₂ O ₂ , di-tert-butyl peroxide (CH ₃ ) ₃ COOC (CH ₃ ) ₃ and Tert-butyl peroxyisopropyl carbonate C ₈ H ₁₆ While O ₄ is known to increase the polymerization reaction rate, such other organic peroxides were significantly improved, high, very high or maximal transparency (or significantly reduced) , Low, very low or minimal haze values), or fail to facilitate or achieve the production of SAN resins. Such other organic peroxides may also fail to facilitate or achieve the production of other desirable properties such as SAN resins with high intrinsic viscosity.

  In this disclosure, the term “set” is used in accordance with known mathematical definitions (eg, Peter J. Eccles, Cambridge University Press (1998), An Introduction to Mathematical Reasoning: Numbers, Sets, and Functions, “Chapter 11: Properties of Finite Sets” (for example, in a manner corresponding to that described in page 140), mathematically at least one concentration Defined as a non-empty finite organization of the indicated elements (ie, the series defined herein may correspond to a set of one component or single element or a set of multiple elements) The

Exemplary Manufacturing Method Embodiment FIG. 1 illustrates a highly transparent / low clouded SAN resin or 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent, according to an embodiment of the present disclosure. 1 is a flowchart of a process 100 for manufacturing a composition. In one embodiment, the process 100 includes a given (eg, predetermined) amount of styrene monomer, acrylonitrile monomer, and a suitable solvent, suitable to contain a given (eg, given) mass of chemical components under consideration. A first process portion 110 is included that includes mating in a polymerization reaction vessel or chamber having a volume. In an exemplary embodiment, the vessel can be a stainless steel reactor having an internal volume of, for example, about 5 liters or more (eg, about 10, 20, 50, 100, 1000 or 2000 liters). The vessel may be maintained in an inert (eg, nitrogen) atmosphere at a desired pressure (eg, about 1 bar) during one or more portions of the process 100 in a manner understood by those skilled in the art. Depending on the details of the embodiment, the solvent can include one or more alcohols, ketones, aromatic hydrocarbons or other solvents. For example, the solvent can include methanol, ethanol, methyl ethyl ketone (MEK), methyl isobutyl ketone, toluene, xylene, tetrahydrofuran, dimethylformamide (DMF) and / or another material in which the styrene monomer and acrylonitrile monomer are soluble. .

  The second process portion 120 includes introducing a given (eg, predetermined) amount of chain transfer agent and / or molecular size control agent, such as a mercaptan, into the vessel and blending or mixing the vessel contents. Including. In an exemplary embodiment, the chain transfer agent / molecule size control agent may comprise or be tertiary lead decyl mercaptan (TDM). One skilled in the art will appreciate that the second process portion 120 can include other chain transfer agents / molecule size control agents (eg, different mercaptans), depending on the details of the embodiment.

  Third process portion 130 introduces a given (eg, predetermined) amount of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent into the container, and further blends or mixes the container contents. Including that. Depending on the details of the embodiment, the amount of 1,1-di (tert-butylperoxy) cyclohexane introduced into the vessel may range from about 5 to 500 ppm (million million) relative to the total mass or weight of styrene and acrylonitrile monomers in the vessel. Fraction). For example, in various embodiments, the amount of 1,1-di (tert-butylperoxy) cyclohexane introduced into the container can be about 10-400 ppm (eg, about 50-300 ppm or about 100-200 ppm). In general, the amount of 1,1-di (tert-butylperoxy) cyclohexane under consideration is the desired, intended or targeted (a) polymerization time; (b) polymerization temperature, as further described in detail below. Or temperature range; (c) degree, level, scale, ratio or efficiency of polymerization conversion; and (d) the total of styrene and acrylonitrile monomers under consideration, taking into account one or more of the SAN resin haze values. It can be selected or determined based on mass or weight.

  In various embodiments, the process 100 according to the present disclosure can be used as a sacrificial agent in the absence of or in the absence of another chemical, composition or compound that can act as a polymerization initiator, catalyst, or sacrificial agent. Including the use of 1,1-di (tert-butylperoxy) cyclohexane. However, in certain embodiments, 1,1-di (tert-butylperoxy) cyclohexane is used as a sacrificial agent to produce SAN resins having reduced, low or very low haze values according to the present disclosure. One or more other chemicals that can be used and can act as polymerization initiators, catalysts or sacrificial agents (eg, in a manner that lowers the polymerization temperature and / or increases the polymerization conversion) It can be introduced into the reaction vessel (eg, before, during or after the third process portion 130). However, in embodiments where the reaction vessel contains 1,1-di (tert-butylperoxy) cyclohexane and one or more other chemicals that can act as a polymerization initiator, catalyst or sacrificial agent, The amount or concentration (eg, weight percentage) of di (tert-butylperoxy) cyclohexane is such as to yield a SAN resin having a significantly reduced, low, very low or essentially minimal haze value. Should be superior or overwhelming in the amount or concentration of other chemicals. For example, the amount or concentration of 1,1-di (tert-butylperoxy) cyclohexane should be about 80%, 90%, 95% or 98% greater than the amount or concentration of such other chemicals .

  The fourth process portion 140 includes heating the vessel contents to a temperature sufficient to initiate the polymerization reaction. In various embodiments, the fourth process portion 140 moves the vessel contents to a temperature of about 85-135 ° C (eg, about 90-130 ° C or about 90-120 ° C, 100-115 ° C, or about 110 ° C). Heating. The fifth process portion 150 may be used to polymerize the vessel contents at a temperature sufficient to sustain the polymerization reaction, or within a temperature range, such as a series of temperatures within one or more of the temperature ranges described above. Maintaining for a given (e.g., predetermined) time. Depending on the details of the embodiment, the polymerization time can be from about 1.0 to about 4.0 hours, such as from about 1.5 to 3.5 hours (eg, about 2.0, 2.5 or 3.0 hours).

  The sixth process portion 160 includes lowering the internal temperature of the vessel to stop further polymerization reactions. In various embodiments, the inner vessel temperature can be cooled below about 80 ° C, such as below about 50 ° C. Finally, the seventh process portion 170 includes collecting or recovering enhanced, high or very high transparency SAN resin from the container.

Typical Examples The following typical examples describe experiments that demonstrate the effects, functions, features, and / or properties of certain SAN resins prepared or manufactured according to embodiments of the present disclosure. Those skilled in the art will appreciate that the scope of the present disclosure is not limited to the following typical examples.

Comparative study example 1
Experiments in Comparative Study Example 1 were conducted to evaluate the conversion rate of the polymerization reaction of styrene monomer and acrylonitrile monomer in the absence and presence of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent at various concentrations. And decided.

SAN resin production and styrene acrylonitrile (co) polymer conversion analysis SAN resins according to embodiments of the present disclosure were produced and analyzed using the following process parts or process steps.

Process Step (i): Introducing Monomers and Reagents The production was carried out under a nitrogen atmosphere. About 1125 grams of styrene monomer, about 375 grams of acrylonitrile monomer, and about 150 grams of ethylbenzene were introduced into a 5-liter reactor or reaction chamber. The pressure in the reactor was maintained at about 1 bar under a nitrogen atmosphere. Ethylbenzene was used as a solvent and viscosity reducing medium for the reaction system. Styrene monomer, acrylonitrile monomer and ethylbenzene were mixed for about 15 minutes to ensure homogeneity. After mixing, about 1.5 grams of tertiary lead decyl mercaptan (TDM) was added as a molecular size control agent or chain transfer agent. In addition, 1,1-di (tert-butylperoxy) cyclohexane was added as a sacrificial agent in various amounts or concentrations detailed below.

  More specifically, in separate experiments, about 0.015 grams (equivalent to 10 ppm based on the total weight of styrene and acrylonitrile monomers), about 0.030 grams (equivalent to 20 ppm), about 0.075 grams (equivalent to 50 ppm) and about 0.150 grams ( Equivalent to 100 ppm), or 0.210 grams (equivalent to 140 ppm) of 1,1-di (tert-butylperoxy) cyclohexane was added to the reactor, after which the reactor contents were further mixed or stirred for about 15 minutes.

Process Step (ii): Polymerizing Styrene and Acrylonitrile Monomers To initiate the bulk polymerization reaction, the resulting mixture present in the reactor is heated to 1,1 using a heating rate of about 2 ° C. per minute. Final temperature of about 140 ° C for experiments in the absence of -di (tert-butylperoxy) cyclohexane, or final of about 110 ° C for experiments in the presence of 1,1-di (tert-butylperoxy) cyclohexane Heated to temperature. The temperature was accordingly maintained at a reaction temperature of about 140 ° C. or about 110 ° C. for a duration of about 1, 2, 3 or 4 hours or polymerization time to cause the polymerization reaction. The polymerization reaction was interrupted or stopped by subjecting the reaction vessel to liquid nitrogen for about 3 minutes or by exposure.

Process Step (iii): Analyze Percent Conversion of Styrene and Acrylonitrile Polymerization A 5 gram SAN sample obtained from the polymerization reaction of styrene and acrylonitrile was collected and completely dissolved in about 100 milliliters of methyl ethyl ketone (MEK). After complete dissolution, the SAN sample was precipitated by introducing and stirring about 50 milliliters of methanol (MeOH) until the SAN contents were completely precipitated. After precipitation, the SAN contents were filtered and dried at a temperature of about 80 ° C. for about 5 hours. The resulting SAN contents were weighed and the percent conversion was calculated.

Results and Discussion Table 1 shows that styrene and acrylonitrile form styrene acrylonitrile resin (SAN) (co) polymers in the absence and presence of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent at different concentrations. The percent monomer conversion is indicated. As shown in Table 1, considering or comparing the results corresponding to any individual reaction time (ie, the same reaction time of about 1 hour, 2, 3, or 4 hours), sacrificed at a reaction temperature of 110 ° C. The percent conversion to SAN polymer in the presence of 1,1-di (tert-butylperoxy) cyclohexane as agent is in the absence of 1,1-di (tert-butylperoxy) cyclohexane at a reaction temperature of 140 ° C. It was higher or significantly higher than the case. In other words, the polymerization reaction of the styrene and acrylonitrile monomers that form the SAN resin is carried out in the presence of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent at a significantly lower temperature (ie, about 110 ° C. versus about 140 ° C. ° C). A lower reaction temperature is desirable to save energy and produce a lower amount of by-products associated with the polymerization reaction. Furthermore, the percent conversion to SAN polymer increased with increasing amount or quantity of 1,1-di (tert-butylperoxy) cyclohexane at the same reaction temperature of about 110 ° C. For example, for a reaction duration of about 3 hours, the percent conversion to SAN polymer is from 1,0-di (tert-butylperoxy) cyclohexane amount or concentration from about 0, 10, 20, 50, 100 to 140 ppm. When increased, it increased from about 35.1, 41.9, 46.8, 62.8, 66.8 to 71.3. Due to the functional activity of 1,1-di (tert-butylperoxy) cyclohexane, from about 35.1 to 71.3 at the same reaction time of about 3 hours at 110 ° C, rather than 140 ° C, at a significantly reduced temperature An increase in percent conversion, or an increase in conversion of about 100% or 2 times, is considered to be significantly unexpected and / or surprisingly good compared to conventional SAN resin polymerization processes. In addition, the use of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent yields the target conversion compared to the polymerization reaction without 1,1-di (tert-butylperoxy) cyclohexane. A reduction in the reaction time required for this can be facilitated or realized. For example, a conversion of about 50% required about 4 hours at a reaction temperature of about 140 ° C. in the absence of 1,1-di (tert-butylperoxy) cyclohexane. By comparison, it takes only about 2 hours at a reaction temperature of about 110 ° C. in the presence of about 140 ppm of 1,1-di (tert-butylperoxy) cyclohexane to achieve a conversion of about 50%. There wasn't. At significantly reduced temperatures (eg, about 21.4% below the reference temperature of about 140 ° C.), the significant reduction in reaction time required to achieve the target conversion is significantly Expected unexpectedly and / or surprisingly good.

  FIG. 2A is a typical graph corresponding to the results shown in Table 1, ppm of 1,1-di (tert-butylperoxy) cyclohexane relative to the percent conversion achieved at 2 hours polymerization time (1, Explain the relationship between 1-di (tert-butylperoxy) cyclohexane and the total weight of styrene and acrylonitrile monomers mixed or blended with or exposed to it. FIG. 2B is another exemplary graph corresponding to the results shown in Table 1, where ppm of 1,1-di (tert-butylperoxy) cyclohexane versus percent conversion achieved at a polymerization time of 3 hours. Explain the relationship between the total weight of styrene and acrylonitrile monomers mixed or blended with or exposed to 1,1-di (tert-butylperoxy) cyclohexane. As shown in Table 1 and Figures 2A and 2B, respectively, polymer conversion is when low concentrations of 1,1-di (tert-butylperoxy) cyclohexane (eg about 5, 10 or 20 ppm) are considered Are significantly improved and the concentration of 1,1-di (tert-butylperoxy) cyclohexane is further increased (eg, above about 30, 40, 50, 80, 100, 120, 140 or more ppm) And very significantly or dramatically improved.

Conclusion The results obtained from Comparative Study Example 1 show that methods, processes or techniques for preparing or producing SAN resins according to various embodiments of the present disclosure are provided by sacrificial agents, adjuvants and Due to the activity, functionality or characteristics of the quasi-catalyst, it can cause a significant or substantial increase in the percent conversion of styrene and acrylonitrile monomers at significantly reduced reaction temperatures to form SAN resins. Suggest that you can.

Comparative Example 2
Production of Styrene Acrylonitrile Resin A SAN resin according to an embodiment of the present disclosure was produced using the following process parts or process steps.

Process Step (i): Introducing Monomers and Reagents The production was carried out under a nitrogen atmosphere. About 1125 grams of styrene monomer, about 375 grams of acrylonitrile monomer, and about 150 grams of ethylbenzene were introduced into a 5-liter reactor or reaction chamber. Ethylbenzene was used as a solvent and viscosity reducing medium for the reaction system. Styrene monomer, acrylonitrile monomer and ethylbenzene were mixed for about 15 minutes to ensure homogeneity. After mixing, approximately 1.5 grams of tertiary lead decyl mercaptan (TDM) was added as a molecular size control agent or chain transfer agent and the reactor contents were further stirred for 15 minutes.

Process Step (ii): Polymerizing the styrene and acrylonitrile monomers To initiate the bulk polymerization reaction, the resulting mixture present in the reactor is heated to about 150 ° C and the reaction temperature is maintained for a duration of about 3 hours. Maintained at about 150 ° C. After polymerization, the temperature was lowered below about 50 ° C. to stop the polymerization reaction.

Process Step (iii): Obtaining Styrene and Acrylonitrile Resins Unreacted monomers, excess reagents and solvents in liquid form were removed from the styrene and acrylonitrile resins using an evaporator under a pressure of about 200 mm Hg. The styrene and acrylonitrile resins were further cured at a temperature of about 70 ° C. for a duration of about 5 hours. The resulting polymer was then crushed and processed to obtain test specimens or samples.

Process stage (iv): Test specimen
SAN resin specimens or samples were prepared for testing purposes. More specifically, SAN specimens were tested for melt flow index (MFI), intrinsic viscosity (IV) and HAZE value. Melt flow index (also known as melt flow rate or melt index) is a measure of the ease of flow of a molten polymer having units of grams of polymer in 10 minutes. The MFI of SAN resin according to the experiment in Comparative Example 3 is ASTM D1238: Standard Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer, p. Measured according to 273-286. The intrinsic viscosity (IV) of the SAN resin was measured according to an in-house protocol. Intrinsic viscosity is a dimensionless value. The HAZE value, which indicates the transparency of SAN resin, is ASTM D1003: Standard Test Method for Haze and Luminous Transmittance of Transparent Plastics, p.205-210 Determined according to In brief, the HAZE value is calculated as a percentage of the diffuse transmittance relative to the total transmittance obtained from the transmittance meter. Lower HAZE values correspond to SAN resins with higher transparency or better appearance.

  The characteristics and properties of the SAN resin test piece corresponding to Comparative Example 2 are shown in Table 2 below.

Comparative Example 3
In Comparative Example 3 , SAN resin was prepared (prepared or produced) using the same process part as Comparative Example 2 provided earlier.

However, in Comparative Example 3 , the resulting mixture present in the reactor was heated to about 140 ° C. and maintained at about 140 ° C. as the reaction temperature in process part (ii) for polymerizing styrene and acrylonitrile monomers.

The characteristics and properties of the SAN resin test piece of Comparative Example 3 are shown in Table 2 below.

Example 2
In Example 2, a SAN resin was prepared (prepared or produced) using the same process part as in Comparative Example 2 provided earlier.

  However, in Example 2, about 0.075 grams of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent and about 1.5 grams of tertiary lead decyl mercaptan (TDM) as a molecular size control or chain transfer agent. Monomer and reagents were added into the reactor in process part (i). In other words, about 50 ppm (parts per million) (ppm based on the total weight of styrene and acrylonitrile monomers) 1,1-di (tert-butylperoxy) cyclohexane was further introduced into the reactor as a sacrificial agent. Further, in Example 2, the resulting mixture present in the reactor was heated to about 130 ° C. and maintained at about 130 ° C. as the reaction temperature in process part (ii) for polymerizing styrene and acrylonitrile monomers.

  The characteristics and properties of the SAN resin test piece of Example 2 are shown in Table 2 below.

Example 3
In Example 3, SAN resin was prepared (prepared or produced) using the same process part as Example 2 provided previously.

  However, for Example 3, about 0.150 grams of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent was added into the reactor in process part (i) where the monomer and reagent were introduced. In other words, about 100 ppm (parts per million) (ppm based on the total weight of styrene and acrylonitrile monomers) 1,1-di (tert-butylperoxy) cyclohexane was further introduced into the reactor as a sacrificial agent.

  The characteristics and properties of the SAN resin test piece of Example 3 are shown in Table 2 below.

Example 4
In Example 4, SAN resin was prepared (prepared or produced) using the same process part as Example 3 provided previously.

  However, for Example 4, about 0.210 grams of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent was added into the reactor in process part (i) where the monomers and reagents were introduced. In other words, about 140 ppm (parts per million) (ppm based on the total weight of styrene and acrylonitrile monomers) 1,1-di (tert-butylperoxy) cyclohexane was further introduced into the reactor as a sacrificial agent.

  The characteristics and properties of the SAN resin test piece of Example 4 are shown in Table 2 below.

The results and study table 2 based on the above results show the characteristics and properties of the SAN resin test specimens obtained by the process steps described in Comparative Examples 2 and 3, Example 2-4 . In particular, the SAN resin specimens were tested for melt flow index (MFI), intrinsic viscosity (IV) and HAZE value (corresponding to% haze value). As shown in Table 2, the MFI of the SAN resin or test piece (ie, Comparative Example 2 and Comparative Example 3 ) produced or prepared in the absence of 1,1-di (tert-butylperoxy) cyclohexane Is approximately or generally the same as the MFI value of the produced or prepared SAN resin or specimen (ie, Examples 2-4) in the presence of 1,1-di (tert-butylperoxy) cyclohexane as the sacrificial agent. It was the same. Furthermore, with respect to the increased amount or concentration of 1,1-di (tert-butylperoxy) cyclohexane used (ie increase from 50, 100 to 140 ppm in Examples 2, 3 and 4 respectively), the MFI value There was no significant difference or essentially no significant difference.

  Intrinsic viscosity values of produced or prepared SAN resins or specimens in the absence or presence of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent are approximately similar or relatively It was the same.

As shown in Table 2, the HAZE value of SAN resin or test piece (ie, Comparative Example 2) produced in the absence of 1,1-di (tert-butylperoxy) cyclohexane at a reaction temperature of 150 ° C. is about 0.68. (Ie about 68%). When the reaction temperature was lowered from about 150 ° C. (ie, Comparative Example 2) to about 140 ° C. (ie, Comparative Example 3 ), the HAZE value of the SAN resin decreased from about 0.68 to about 0.56. This result shows that lowering the reaction temperature can lower the HAZE value due to the lower or reduced amount of by-products associated with the polymerization reaction or produced from the polymerization reaction, or more transparent It was shown that a new resin can be produced. 1,1-di (tert-butylperoxy) at a concentration of about 50 ppm (ie Example 2), about 100 ppm (ie Example 3) and about 150 ppm (ie Example 4) at a reaction temperature of about 130 ° C. The HAZE values of SAN resins or specimens produced in the presence of cyclohexane were about 0.48, 0.28 and 0.18, respectively. This result shows that increasing the concentration of 1,1-di (tert-butylperoxy) cyclohexane can significantly, significantly or dramatically reduce the HAZE value, or more transparent, improved transparency Suggested that can produce SAN resin. Due to the presence of 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent during the course of the polymerization reaction, such a significant improvement in the HAZE value was unexpected or surprising. The presence of 1,1-di (tert-butylperoxy) cyclohexane led to the lower reaction temperature required (about 150 or 140 ° C vs. about 130 ° C). More for energy savings and for reduced, lower or lower amounts of by-products resulting from or derived from polymerization reactions that can cause haze or contribute to undesirable high HAZE values A low reaction temperature was desired.

  FIG. 3 is a typical graph corresponding to the results shown in Table 2, where ppm of 1,1-di (tert-butylperoxy) cyclohexane (1,1-di ( tert-Butylperoxy) relationship to the total weight of styrene and acrylonitrile monomers mixed or blended with or exposed to cyclohexane). As shown in Table 2 and Figure 3, HAZE values are significantly reduced even when small concentrations of 1,1-di (tert-butylperoxy) cyclohexane (eg, about 5, 10 or 20 ppm) are considered (Or the transparency of the SAN resin is significantly improved, enhanced or increased) and the 1,1-di (tert-butylperoxy) cyclohexane concentration is further increased (eg, about 30, 40, 50, 80, 100 , 120, 140 or more ppm), HAZE values are significantly significantly or dramatically reduced (or SAN resin transparency is improved, improved or increased very significantly or dramatically) )

Conclusion The results obtained from Comparative Example 2 and the corresponding individual Comparative Examples 3, Examples 2-4 include 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent, according to various embodiments of the present disclosure. , Methods, processes or techniques for preparing or producing styrene acrylonitrile resin (SAN) can be improved, improved or superior to SAN resin without compromising the physical properties or characteristics of other SAN resins Suggests that it can produce or achieve high transparency.

Further exemplary manufacturing considerations In some embodiments, (a) a series of haze values, curves or functions for 1,1-di (tert-butylperoxy) cyclohexane concentration and one or more temperature values or temperature ranges; And / or (b) a series of polymer percent conversions or polymer conversion curves or functions that are generated, stored, retrieved, or recalled to target, intended, or adjusted / customized SAN It can assist in the determination or selection of manufacturing process parameters that can result in resin manufacture. The production of SAN resins with targeted, intended or customized haze values can be targeted or can occur within or near the desired (eg, minimum) polymerization time. One or more of the values, curves or functions described above are set to automatically or semi-automatically achieve one or more aspects of the enhanced transparency SAN resin manufacturing process according to one embodiment of the present disclosure; It can be created, stored, retrieved or recalled on or using an automated system such as a computer or electronic system.

  FIG. 4 shows improved or high transparency / reduced or low haze SAN resin using 1,1-di (tert-butylperoxy) cyclohexane as a sacrificial agent according to another embodiment of the present disclosure. Alternatively, it is a flowchart of a process 200 for manufacturing a composition. The first process portion 210 retrieves (eg, from a computer readable medium, eg, memory) or receives (eg, as a result of user input, a user's target or desired haze or transparency value). Can be received by interacting with an input device, such as a touch screen display, computer mouse or keyboard); the second process portion 220 can include at least one target or desired polymerization reaction temperature and Retrieving or receiving a target or desired polymerization time.

  The third process portion 230 is a 1,1-di (tert-butylperoxy) cyclohexane concentration (eg, expected to result in the production of a SAN resin having a target or desired haze or transparency value. Determining the amount of styrene monomer and acrylonitrile monomer under consideration (for example, relative to the total mass or weight of such monomer). The third process portion 230 is one or more relationships between the haze or transparency value and the 1,1-di (tert-butylperoxy) cyclohexane concentration with respect to the polymerization reaction temperature, and optionally targeted Alternatively, in view of the desired polymerization reaction temperature, it may involve recalling accumulated data and / or functions that estimate or establish the selection of 1,1-di (tert-butylperoxy) cyclohexane concentration. The fourth process portion 240 may include determining a polymerization time that meets or is close (eg, as close as possible) to the target or desired polymerization time. The fourth process portion 240 optionally corresponds to, or is expected to correspond to, or at least, the desired polymer percent conversion with respect to the target or desired polymerization reaction temperature under consideration. It may include confirmation or selection of the polymerization time.

  The first through fourth process portions 240 include a series of process parameters for SAN resin manufacture or production (eg, 1,1-di (tert-butylperoxy) cyclohexane concentration and one or more polymerization reaction temperatures, Determination of polymerization time or other parameters). The fifth process portion 250 uses the process parameters determined in conjunction with the first to fourth process portions 240 to improve or increase transparency / reduced or low haze, target haze. Or manufacturing a SAN resin having a transparency value. The fifth process portion 250 may include one or more process portions according to embodiments of the present disclosure, such as process 100 described above with respect to FIG.

  One or more aspects of the second process 200 described with respect to FIG. 4 may be programmed or designed in detail to perform the specific tasks described above, eg, by fulfilling stored program instructions. It can be automated using a computer system, control system or state machine, or can be performed based on a computer and correspondingly.

  In order to address at least one of the previously presented problems, specific embodiments of the present disclosure are described above. While features, functions, processes, process parts, advantages and modifications associated with certain embodiments have been described within those embodiments, other embodiments may also exhibit such advantages and all Such advantages do not necessarily have to be shown so that embodiments are within the scope of the present disclosure. It will be appreciated that some of the features, functions, processes, process parts, advantages and modifications disclosed above can be desirably tailored to other different methods, processes, systems or applications. The features, functions, processes, process parts or modifications disclosed above, as well as the various presently unforeseen or unexpected changes, modifications, changes or improvements made by those skilled in the art are claimed in the following claims. Included in the range.

Claims (11)

A method for producing a styrene acrylonitrile (SAN) resin having a desired haze value ,
Changing the concentration of the polymerization initiator present during the polymerization reaction between the styrene monomer and the acrylonitrile monomer carried out in a solvent at a temperature of 85 to 130 ° C. according to the desired haze value,
The initiator is 1,1-di (tert-butylperoxy) cyclohexane , and the haze value of the SAN produced is inversely correlated with the concentration of the initiator, and the solvent is a ketone, alcohol, or aromatic carbonization The method of being hydrogen . The method of claim 1, wherein the haze value is less than 0.2 when the concentration of the initiator during the polymerization reaction is greater than 130 ppm. The method of claim 1, wherein a concentration of the initiator present during the polymerization reaction of 80 to 130 ppm corresponds to the haze value of 0.35 to 0.2. The method according to claim 1, wherein the polymerization reaction further comprises a chain transfer agent. The method of claim 4, wherein the chain transfer agent is terrestrial decyl mercaptan. The method according to claim 1, wherein the solvent is ethylbenzene, methanol, ethanol, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, tetrahydrofuran, or dimethylformamide. Of styrene monomers and acrylonitrile monomers, to produce the desired styrene acrylonitrile (SAN) resin haze value, a method of computer-based method based on the computer is executed on a computer system, and
Including determining a series of process parameters for producing a SAN resin,
Wherein determining the set of process parameters,
Receiving a target haze value in response to user input directed to the computer system;
Determining the amount of styrene monomer and acrylonitrile monomer; and with respect to the amount of styrene monomer and acrylonitrile monomer, the 1,1-di (tert-butylperoxy) cyclohexane concentration corresponding to the desired haze value of the SAN resin produced look including to automatically determine,
The method wherein the haze value of the manufactured SAN is inversely correlated with the concentration of the 1,1-di (tert-butylperoxy) cyclohexane . Wherein determining the set of process parameters, in response to user input indicated to the computer system, further comprising receiving a polymerization time of polymerization reaction temperature and the target and at least one target, claim 7 The method described. 9. The method of claim 8 , wherein determining the set of process parameters further comprises determining a polymerization time that is expected to correspond to a target minimum polymer percent conversion. 10. A method according to any one of claims 7 to 9, wherein the 1,1-di (tert-butylperoxy) cyclohexane concentration is determined to be greater than 130 ppm when the desired haze value is less than 0.2. The method according to any of claims 7 to 9, wherein the 1,1-di (tert-butylperoxy) cyclohexane concentration is determined to be 80 to 130 ppm when the desired haze value is 0.35 to 0.2. .

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