Method and apparatus for preparing intermediate polyester resin

• US 3,985,712 A
• Filed: 02/12/1975
• Issued: 10/12/1976
• Est. Priority Date: 02/12/1975
• Status: Expired due to Term

• Current Assignee: Owens- Corning Fiberglas Technology Incorporated (Owens Corning)
• Original Assignee: Owens-Corning Fiberglas Corporation
• Inventors: Garst, John M.
• Primary Examiner(s): Wayner, William E.
• Application Number:
  US05/549,216
• Time in Patent Office: 608 Days
• Field of Search: 236/46, 236/15 B, 432/18, 235/151.12, 23/230 A, 260/75 M, 260/75 UA
• US Class Current: 528/271
• CPC Class Codes: B01J 19/0013 Controlling the temperature of the process
• CPC Class Codes: B01J 2219/00063 of the reactants
• CPC Class Codes: B01J 2219/0009 Coils
• CPC Class Codes: B01J 2219/00168 controlling the viscosity
• CPC Class Codes: B01J 2219/00177 controlling the pH
• CPC Class Codes: B01J 2219/00184 controlling the weight of reactants in the reactor vessel
• CPC Class Codes: C08G 63/785 characterised by the apparatus used
• CPC Class Codes: G05D 23/1904 variable in time
• CPC Class Codes: G05D 23/20 with sensing elements having variation of electric or magnetic properties with change of temperature G05D23/13 takes precedence

Abstract

A programmed method for the preparation of an intermediate polyester resin is disclosed. The process is monitored and controlled by a supervisory on line computer which supervises the three phases of the process: the charging phase; the temperature elevation phase and the cooking phase. During the critical temperature elevation phase the supervisory program assures that a runaway exothermic chemical reaction does not occur. This is accomplished by periodically reading batch temperature and comparing it with an emperically determined temperature time curve stored within the program. Heat input or removal is then ordered depending upon the relationship of the batch temperature and the temperature time curve.

Claims

1. A programmable method for raising the temperature of a composition of matter which characteristically generates exothermic heat comprising:

a. providing a time synchronized reference signal corresponding to a desired temperature vs. time variation pattern,

b. applying a first rate of heat input to said composition of matter,

c. progressively increasing the heat input rate at scheduled time intervals,

d. sensing the temperature of said composition of matter at each time interval and providing a signal representative thereof,

e. comparing said signal with the time synchronized reference signal corresponding to the scheduled time interval.

f. determining any divergence of the sensed composition temperature greater than the desired temperature,

g. imposing a programmed logic upon said heat input schedule responsive to the determined temperature divergence until the sensed composition temperature converges with the desired temperature,

h. repeating steps c through g until the desired elevated temperature is attained.

2. In a process for producing an intermediate polyester resin by reacting at least one polyol with at least one polybasic acid, the method of elevating the reactant temperature according to a desired temperature history comprising,

a. providing a predetermined reactant temperature vs. process time variation pattern,

b. applying a first rate of heat input to said reactants,

c. incrementally increasing said rate of heat input to said reactants at given process time intervals,

d. sensing the reactants'"'"' temperature for each process time interval,

e. determining any divergence of the sensed temperature greater than the predetermined temperature for each process time interval,

f. modifying the heat input schedule upon determining such divergence of the sensed reactants'"'"' temperature by,

3. incrementally reducing the rate of heat input to said reactants'"'"' at specified clock time intervals,sensing and storing the reactants'"'"' temperature for each clock time interval,comparing for each increment of clock time the sensed reactants'"'"' temperature with the previously stored temperature,repeating steps (1) through (3) until the reactants'"'"' temperature convergingly approaches the predetermined temperature for the process time interval,

g. resuming the incremental increase of the rate of heat input to the reactants when the reactants'"'"' temperature substantially equals the predetermined temperature for the process time interval.

4. In a process for producing an intermediate polyester resin by reacting at least one polyol with at least one polybasic acid, the method of elevating the reactants'"'"' temperature according to a desired temperature history comprising,

A. providing a desired reactant temperature-time history,

B. applying an initial rate of heat input to said reactants,

C. establishing a first reference time increment schedule and at each time increment thereof,increasing the rate of heat input to said reactants,

sensing the temperature of said reactants,comparing the sensed reactants temperature to the desired temperature for the given time increment,determining any divergence of the reactants temperature above the scheduled temperature,modifying the heat input program upon determining such divergence of the reactants temperature by establishing a second reference time increment schedule and at each time increment thereof,

a. reducing the rate of heat input to said reactants,

b. sensing and storing the reactants temperature,

c comparing the reactants temperature with the previously stored temperature,

d. repeating steps (a) through (c) until the reactants temperature convergingly approaches the desired set point temperature for the first reference time increment,

e. resume increasing the rate of heat input in accordance with said first reference time increment schedule.