Progress 09/01/19 to 07/19/22

Outputs
Target Audience:Target audience of the work proposed in this Phase II include 1. Chemical companies that specialize in making polymeric resins for lens uses. Examples of these companies include - Mitsui Chemicals, PPG industries, Mitsubishi Chemical Holdings, Covestro, SABIC etc. Notably, there are only a few companies in the world which specialize in making these resins. Also, the effort to make bio-based or greener optical resins has been initiated or desired and the outcome of this project will be a great fit for that initiative. 2. Lens manufacturing companies (including optical labs) that specialize in making ophthalmic or camera lenses. These include Essilor, Hoya, Kodak, Signor Armorlite, Zeiss etc. Several Asian OEMs now do a majority of lens manufacturing for the world. 3. Companies that use lenses in their retail products. Many companies fall in this category, including, Costco, Walmart, LensCrafters, Warby-Parker on the eyewear side, and Apple, Samsung, Google etc. on the camera lenses. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We hired a process technician to work on the molding process who joined us in January 2021 to work on this project. She has Masters in Chemistry and is now on STEM extension to work on this project. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Aim 1.4: Molding of bioplastic into films; measurement of R.I. and Abbe value:This goal was completed by making thin films from MDI based polymer and getting measured the R.I. and Abbe value of the films. Molding of bioplastic into thin films: We have made several batches of polymer by adding a UV absorber with reactive group to the reaction system of the existing Bioplastic as given below. Following synthetic protocol (Figure 1) is a representative example of the one-pot synthesis of rigid, optically clear polyurethane. The diol, isosorbide, reacts with three different diisocyanates including a high refractive index (1.587), Diphenylmethane diisocyanate, (MDI), in the presence of a catalyst, UV absorber and solvent followed by reacting with a crosslinker, glycerol, in the same pot. Aromatic moieties are known to impart hydrophobic behavior to a molecule, increase the refractive index of the polymer, and lower the dispersion (Abbe value). The pristine polymer chunks were pressed in Carver press at certain temperature and pressure to make a polymer film. The film was then soaked into methanol for overnight to replace the leftover high boiling solvent in the polymer. The film was repressed one more time to squeeze out the methanol and vacuum dried in a convection oven at 120 °C. The dry film was then pressed in the Carver in between chrome plated and heat-treated steel plates to make thin transparent films of thickness ~ 0.5 mm. Such transparent thin films with insignificant amount of surface irregularities are required to make a bump free lens. The process in Chart 2 was repeated several times to make enough transparent thin films to make a thick compact disc by stacking and pressing those thin films in the Carver. The disc was made into a lens by pressing them in between glass molds. However, before molding final lens, thin film was sent for R.I. and Abbe value measurement. Measurement of R.I. and Abbe value: The thin film was sent to Metricon Corp., Pennington, NJ, for the measurement of R.I. and Abbe value. The R.I. of the sample was measured at three different wavelengths: 448, 532 and 633 nm and the measured R.I. was 1.557 and the Abbe value was 36.2. Aims 1.5, 2.2 & 2.3: 2nd generation high index monomers & development of Rx lenses molding: We have successfully made high refractive index monomers and incorporated them by cast molding followed by compression molding to yield high refractive index, high Abbe Rx lenses which is the best bio-based lens. 2nd Generation high index monomers: In order to increase the refractive index of bio-based monomer, isosorbide, and to increase the bio-based content in the final thermoset material, we need to derivatize isosorbide and make new monomers based on isosorbide. A derivative of Isosorbide, Isosorbide-3-mercaptopropionate (I3DT) was synthesized to overcome this limitation as previously reported. A high index sulfur containing crosslinker, 1,3-bis(2-mercaptoethylthio)-2-mercaptopropane (trithiol) was synthesized for the reaction as previously reported. The goal is to find high refractive index and Abbe second generation polymers via less challenging and easily scalable routes. All the monomers used here are either easily commercially available in kg quantities or easily synthesized in large quantities. Optimization of cast molding process: We have implemented the cast molding followed by the compression molding process to make high index lenses. These high index lenses were based on the urethane chemistry using two different diisocyanates, H12MDI and HMDI, during cast molding inside the glass molds (Table 4). In this polythiourethane reaction, the monomer mixture was poured into the concave side of a mold with specific power, eg. 3.0 D, lined with two 1 mm thick and 50 mm diameter aluminum spacer (Picture 3). The thickness of the spacer determines lens edge thickness. The temp gradually reached the set point (120 °C)within an hour and left the solution filled mold assembly inside the oven for 20 h to cure. Finally turned the heater off and cooled it down to 50 °C under vacuum before exposed the film to room temperature. The film turned out to be colorless, transparent with little shrinkage (Picture 4). Compression molding of the cast molded lens: The cast molded film was reshaped into a Rx lens by pressing in the Carver. The glass mold containing the cast molded film was lined with a spacer of desired thickness and diameter and a top glass mold with the right prescription was placed on top. The entire assembly was heated in the Carver at 130-150 °C and pressed at 500 pounds pressure. The resulted Rx lens was transparent with little or no bumps, and free of bubbles. The manual lensometer (American Optical) displayed clear cross-hair image of the target (picture 5) indicating bumpiness free molded Rx lenses that was mounted in frame (Picture 6). Measurement of R.I. and Abbe value: One of the lenses was sent to Metricon Corp., Pennington, NJ, for the measurement of R.I. and Abbe value. The R.I. of the sample was measured at three different wavelengths: 448, 532 and 633 nm and the measured R.I. was 1.5767 and the Abbe value was 43.1. Aims 3.1 & 3.2: Perform Coating, ISO & ANSI Testing & Evaluate lens Benefit & Wearer Tests: We have successfully molded Rx lenses of Gen 2nd and prior hard coat and AR coating tests formulation and expected to pass these tests on the molded Rx lenses. Based on prior wearer test, we believe that the Gen 2nd Rx lenses are clearer and expected to provide positive feedback from wearer. Data Collected: We have molded Rx lenses of Gen 2nd and they are clearer and dust-free and bump-free due to the cast molding-compression molding processes. As the material possess high refractive index and above average Abbe, the lens can be molded thinner than mid or low-index materials. Above average Abbe will enhance the clear optical region of the Rx lens. Based on our prior experience with the application of hard coat by dip or spin-coating process followed by thermal or UV-curing and application of vacuum deposited metal oxides to create Anti-reflective (AR) stack and the chemicals used in these processes, we tested our molded Gen 2nd Rx lenses with these chemical and solvents such as Methanol, Isopropyl Alcohol, etc to ensure that the lenses are not damaged in any way. We found that the Rx lenses pass these solvent tests. The lens benefit & Wearer Test have been performed with the previous generation material and their results were promising and better than the incumbent polycarbonate lenses. Knowing that the refractive index is high and Abbe is above average, we expect similar results as before with mid-index material and we expect positive feedback from wearers. *Figures, Tables, and Pictures are attached at: https://drive.google.com/file/d/1NkODpvtAD4-HxRX75sFV9VltVToIeRHO/view?usp=sharing

Publications

Progress 09/01/20 to 08/31/21

Outputs
Target Audience:Target Audience Target audience of the work proposed in this Phase II include 1. Chemical companies that specialize in making polymeric resins for lens uses. Examples of these companies include - Mitsui Chemicals, PPG industries, Mitsubishi Chemical Holdings, Covestro, SABIC etc. Notably, there are only a few companies in the world which specialize in making these resins. Also, the effort to make bio-based or greener optical resins has been initiated or desired and the outcome of this project will be a great fit for that initiative. 2. Lens manufacturing companies (including optical labs) that specialize in making ophthalmic or camera lenses. These include Essilor, Hoya, Kodak, Signor Armorlite, Zeiss etc. Several Asian OEMs now do a majority of lens manufacturing for the world. 3. Companies that use lenses in their retail products. Many companies fall in this category, including, Costco, Walmart, LensCrafters, Warby-Parker on the eyewear side, and Apple, Samsung, Google etc. on the camera lenses. Changes/Problems:The second half of USDA funds were made available to us in September 2021. Earlier in 2021, we hired a post-doctoral scientist to help in the high index monomer synthesis and scale up. Unfortunately, after several months the post-doctoral scientist declined due to personal reasons. Hiring personnel during the COVID pandemic has been very difficult and have decided to raise venture funds and hire manufacturing personnel for scale up. Some to the timelines were shifted due to supply chain issues and lack of resources. Aim 1.4: Resolutions of Problems Encountered The high index polyurethane made with MDI exhibits two different phases causing opaque regions in the lens. A potential resolution to this problem is to make MDI-isosorbide adduct followed by reacting with diisocyanates to form high index, high Abbe value polyurethane. During processing of thin films and thick compact discs between 304 stainless steel cause scratch, indent and metal shards embedded lowering final lens quality. A potential resolution to this problem is to use Tool Steel (A2) that can be heat treated, chrome plated and surface polished to make them hard and scratch-resistant. The polymer films made between such chrome steel plates were found to be devoid of surface defects. Aim 1.5: Resolutions of Problems Encountered The mold assembly with the monomer solution was kept upright position inside the convection oven during the cast molding process. The glass molds with the spacer and the monomer were wrapped with high temperature tapes on the edge in order to stop the liquid monomer to come out from the bottom. However, the tape was unable to prevent the liquid to ooze out from the bottom of the molds at the beginning of the polymerization reaction. The liquid monomer mixture was even heated for a longer time to make a viscous solution in an anticipation that the viscous solution would require longer time than the solidification of the liquid monomer into a thermoset. All attempts failed to stop the leakage. Hence binder clips were used to hold the molds tightly to retain the liquid inside the spacer. What opportunities for training and professional development has the project provided?We hired a process technician to work on the molding process who joined us in January 2021 to work on this project. She has Masters in Chemistry and is now on STEM extension to work on this project. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?Task 1: Aim 1.4: Continue on scale up - Revise Bioplastic Synthetic Process Task 1: Aim 1.5: Continue to create a second-generation polymer with higher refractive index Task 2: Aim 2.2: Continue to optimize the molding process of the repeatability and pilot scale production Task 2: Aim 2.3: Develop a molding process for the high index and high Abbe polymer Task 3: Aim 3.1: Perform Coating, ISO and ANSI testing Task 3: Aim 3.2: Evaluate patient benefit and customer satisfaction via wearer tests

Impacts
What was accomplished under these goals? IMPACT:Myopia boom coupled with need for sustainable eyeglass with improved properties over existing polycarbonate eyeglasses have prompted Novol to develop corn-derived polymer for sustainable eyeglass to reduce carbon footprint and strengthen bio-based economy. Isosorbide, corn-based sugar, is converted to bioplastic that is molded to eyeglass lenses which exhibit excellent optical properties with low chromatic aberration, key downside seen in polycarbonate lenses. Polyurethane synthesized from isosorbide possesses mid-refractive index, high Abbe value that minimizes chromatic aberration (color dispersion). Bioplastic prescription (Rx) lenses made using green process can significantly reduce landfill lens swarf wastegenerated in conventional lens cutting processes and reduce turnaround time for delivering completed pair of eyeglass lenses. We have completed specific aims as outlined in Phase II work plan towards minimum viable product (MVP) (Table 1). The combination of excellent optical properties not available in any current commrecial lens materials along with lightweight makes bio-based sustainable products a potential candidate for next generation eyeglass lenses, and long term, for high-definition camera lenses. Our goal in Phase II is to build commercially viable process, scae up high index polymer, and molding Rx lenses. Given trade-off of refractive index (R.I.) & Abbe value, we have made2nd generation material with enhanced mechanical, thermal properties and stability in boiling water. We are currentlyraise funds from venture capitals based on gen 1 material previously developed at Novol. Specific Aims: Background: Novol has developed a synthetic procedure of crosslinked polyurethane from corn-derived isosorbide and molding process to convert these polymers to prescription (Rx) lenses with good optical properties and 90% final product yield. Molding Rx lenses require precipitated pristine polymers with DMA solventwere pressed into thin films followed by multiple methanol exchanges. Films after vacuum drying were stacked together and pressed to make discs before molding to Rx lens. Vacuum drying polymer films at high temperature removed residual methanol. Aim 1.4: Optimize molecular weight & yield; processing; and Rx lens molding:This goal was completed by reacting isosorbide and aromatic/aliphatic diisocyanates andUV-absorber/antioxidant to enhance refractive index/Abbe value; mold bump-free discs; and Rx lens. Optimize molecular weight & yield:Data Collected: Reaction conditions and addition of monomers were optimized to produce high molecular weight and yield.We made several batches of polymer by adding reactive UV-absorber to the existing Bioplastic. Figure 1 givesone-pot synthesis of rigid, optically clear polyurethane. Isosorbidereacts with three different diisocyanates including high refractive index (1.587), Diphenylmethane diisocyanate, (MDI), in presence of catalyst, UV-absorber and solvent and the with crosslinker, glycerol. Aromatic moieties impart hydrophobic behavior, increase refractive index, and lowers dispersion (Abbe value). Antioxidant BHT used earlier to aid yellow color reduction affected polymer molecular weight.Multifunctional antioxidant (Figure 2) was designed with two hydroxyl groups for reaction and keeping hindered hydroxyl group unreacted (Table 2). Optimize Processing:Data Collected: Solvent exchange, molding thin films, stacking thin films to mold thick slabs was developed so that a viable way to mold bump-free discs could be scaled up.In Chart 2, pristine polymer chunks were pressed at certain temperature and pressure to form film that was soaked in methanol overnight to replace DMA solvent. Film was pressed to remove methanol and vacuum dried at 120 °C. Film was pressed between chrome plated steel to make thin (0.5mm) transparent films with insignificant amount of surface irregularities that are necessary to make bump free Rx lens. However, MDI polymers showed two different phases, transparent and opaque. The phase separation is due to three different diisocyanates used in reaction system that reactdifferently depending on their reactivity. Optimize Rx lens molding:Data Collected: The thin films exhibited two phases: transparent and opaque as shown in Picture 1. Several transparent thin films were stacked to make thick compact disc (Picture 2 (left)). The disc is optically clear, yellow in color and brittle due to repeated processing. Rx lens was made from the disc (Picture 2 (right)). The Rx lens is optically clear, slight yellow and transparent with predetermined prescription. We have built prototype assembly with bolsters to hold and align glass moldsso that compression molding thermoplastic discs accurately and with correctthickness can be achieved. Discussion of Results: The UV absorber/antioxidant produced colorless, optically transparent, tough material in high yield. Films made from MDI polymers have two phases,Rx lenses from transparent phase has slight color and transparent. Key Outcomes: We optimized yield and molecular weight of high index Bioplastic to give non-yellow polymer. The thin/thick discs pressed from chrome plated steel plates areclear, free of contaminant & indent. We will analyze the polymer synthesis to eliminate heterogenous phases and yield homogenous polyurethane. Aim 1.5 & 2.2: 2nd generation high index monomers & Rx lenses molding:This goal is in progress and we have made high refractive index monomers, incorporatein cast molding/compression molding processes to yield high refractive index, high Abbe Rx lens. 2nd Generation high index monomers:To increase isosorbide refractive indexand bio-based content in final thermoset material, new isosorbide monomers were made.Figures 3 and4 show synthesis of new monomers at90+% yield. All monomers used here are commercially available in kg quantities. Optimization of cast molding process:In glass molds, we implemented cast molding/compression molding process to make high index lenses that were polymerized via urethane chemistry. Data Collected: Table 3gives polythiourethane reaction of Isosorbide-3-mercaptopropionate with H12MDI, HMDI and MDI, and trithiol in stoichiometric amount and certain amount of catalyst, DBTL that is heated at 65 °C for 20 min under Argon. Mold assembly is formed with two glass molds,4 mm rubber spacer, and two binder clips (Picture 3). Monomers are filled in mold assembly and placed inside convection oven at 90 °C,then to 110 °C, 120 °C and 140 °C at specific time intervals. After cooling mold assembly, Rx lens was demolded. The lens was colorless and mechanically strongbut covered with bubbles due to the shrinkage(Picture 4). Optimization of compression molding of the cast molded lens:Data Collected: The lens with bubbles (Picture 4) was pressed between stainless-steel plate to give clear slab with few defects (Picture 5 (left)). The clear slab was remolded to Rx lens between two glass molds, 2.25 D and 3.25 D (Picture 5 (right)). The lens was optically clear without any bubbles. Discussion of Results: We madeslab and lens via cast molding/compression molding method. The cast lens with bubbles is molded to slab with no bubbles which was molded toRxlens. Key Outcomes: The results are very promising as the bioplastic cast molding and remoldingwithout any solvents is a greenprocess. We are currently exploring casting lenses without bubbles allowing for short processing and turnaround time to get Rx lenses. Figures, Tables, and Pictures are attached at: https://drive.google.com/file/d/1iZVneO6PEncUM86k6dK_rr04UT8Z5ez5/view?usp=sharing

Publications

Progress 09/01/19 to 08/31/20

Outputs
Target Audience:Target audience of the work proposed in this Phase II include 1. Chemical companies that specialize in making polymeric resins for lens uses. Examples of these companies include - Mitsui Chemicals, PPG industries, Mitsubishi Chemical Holdings, Covestro, SABIC etc. Notably, there are only a few companies in the world which specialize in making these resins. Also, the effort to make bio-based or greener optical resins has been initiated or desired and the outcome of this project will be a great fit for that initiative. 2. Lens manufacturing companies (including optical labs) that specialize in making ophthalmic or camera lenses. These include Essilor, Hoya, Kodak, Signor Armorlite, Zeiss etc. Several Asian OEMs now do a majority of lens manufacturing for the world. 3. Companies that use lenses in their retail products. Many companies fall in this category, including, Costco, Walmart, LensCrafters, Warby-Parker on the eyewear side, and Apple, Samsung, Google etc. on the camera lenses. Changes/Problems:The USDA funds were made available to us in February 2020. Due to COVID-19, Novol was closed from mid-March to mid-May. Some of the timelines were shifted due to this shelter-at-home. Aim 1.1 - 1.4: Resolutions of Problems Encountered Yellow color of the polyurethane and prompt gelation of the reaction mixturewere unexpected. Hence the order and stoichiometry of the reactants helped in preventing gelation. Addition of antioxidants helped in eliminating coloration of the polymer and yielded white polymer. Aim 1.5: Resolutions of Problems Encountered Some of the proposed high index monomers were obtained in low yields and in solid form. Adding short chain carbon links with reactive end groups may potentially lead to liquid high index monomers. Reason for liquid monomers is for cast molding thermosets where dissolution of solid is difficult without any solvents. Aim 2.1: Resolutions of Problems Encountered Mechanical milling techniques like Attrition Mill, Air Classifier Mill (ACM), or Air Jet Micronizing method to pulverize our rigid Biovex generatedheavily contaminated powder in small yield. In addition, these powders were sieved through strainer (Mesh # 100 or higher) to obtain particle diameter in the range of 100-150 µm to produce a bump free lens. An alternate process of spray drying with solvent recovery is being investigated. Aim 2.2: Resolutions of Problems Encountered The polymer powder was contaminated with some dust and fiber particles during the preparation of the molding process which is evident from the Figure 12a) and b). Access to cleanroom or a localized clean area is needed for molding dust-free optical elements. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?Task 1: Aim 1.4: Continue on scale up Task 1: Aim 1.5: Continue to create a second-generation polymer with higher refractive index Task 2: Aim 2.2: Continue to optimize the molding process of the repeatability and pilot scale production Task 2: Aim 2.3: Develop a molding process for the high index and high Abbe polymer Task 3: Aim 3.1: Perform Coating, ISO and ANSI testing to develop a Minimum Viable Product Task 3: Aim 3.2: Evaluate patient benefit and customer satisfaction via wearer tests

Impacts
What was accomplished under these goals? IMPACT Myopia boom coupled with need for sustainable eyeglasses with improved properties over existing polycarbonate eyeglasses (multibillion industry product) have prompted Novol to develop corn-derived polymer for sustainable eyeglass to reduce carbon footprint and strengthen bio-based economy. Isosorbide, a corn-based sugar is converted into polymers which after molding lenses for eyeglass exhibit excellent optical properties with very low chromatic aberration vs. incumbent polycarbonate lenses. Polyurethane (BiovexTM) synthesized from isosorbide possesses mid-refractive index with high Abbe value minimizes chromatic aberration (color dispersion). Prescription (Rx) lenses made using our unique molding process developed in our lab with Biovex can significantly reduce landfill waste remarkably by eliminating lens swarf (shavings) wastes generated in conventional lens cutting processes and reduce turnaround time for delivering completed pair of eyeglass lenses. We have attempted and completed specific aims for this term as outlined in Phase II work plan towards minimum viable product (MVP) (Table 1). Our goal in Phase II is to build commercially viable process, in scaling up of polymer, granulation and molding Rx lenses. In addition we would also make efforts in making high index and Abbe value lenses. Given trade-off between refractive index (R.I.) and Abbe value, we have attempted to strike a balance between these two properties in realizing 2nd generation eyeglass lens material with enhanced mechanical, thermal properties along with stability in boiling water. These Rx lenses will be used in QC testing and wearer trials and their feedback will aid in creating commercial plan. The prototypes will be used to raise capital from venture capitalists and angel investors. Aim Major Activities Data Collected Discussion of Results Key Outcomes 1.1 Optimize Biovex - Amount of solvent Made several batches of high index polymers Learned to balance index and Abbe for high index moiety Made colorless mid- to high-index polyurethane 1.2 Optimize Biovex - Solvent Recycling Found Spray Dryer with Solvent Recovery Distillation of Reaction/Recovery of Purification Solvents Solvent may be reused for processing of the crude polymer 1.3 Optimize Biovex - Agitator Speed Optimization Finalized Reactor Design Reaction dilution and increase in viscosity, optimized agitator speed Aided in completion of polyurethane reaction 1.4 Optimize Biovex - Scale up Reactor design selected Reactor capable of scale up Acquisition of Reactor planned 1.5 Create 2nd-generation high index polymer Made and acquired new monomers High index monomers evaluated in polyurethane synthesis Liquid form high index monomers created 2.1 Optimize polymer milling process Made 100-150µm powder Found Spray Dryer-Solvent Recovery Created fine particles for lens molding 2.2 Optimize molding process and pilot scale production Mold several prescription (Rx) lenses Rx lenses meet the ANSI tolerance specification for Rx Prototype aligners for alignment of glass molds is needed Table 1. Phase II specific aims. Specific Aims Details: Background: Novol has developed Biovex and molding process to mold Rx lenses with good optical properties at 90% yield. Rx lenses exhibit >90% transmission, 1.52 refractive index, Abbe value of 52, and pass FDA Ball Drop Test. To enhance hydrophobicity of polyurethane, aromatic moiety that increase refractive index but lowers light dispersion, was introduced and its percentage optimized in the polymer backbone. Aim 1.1-1.4 Major Activities:Optimize Biovex backbone - solvent required, solvent recovery, agitator speed optimization and scale up Data Collected:Made several batches of polymer by optimizing backbone structure of existing Biovexas given below. Following synthetic protocol (Figure 1) is a representative example of the one-pot synthesis of rigid, optically clear polyurethane. (Figure 2, Table 2) Reaction Optimization:Stoichiometry and addition of reactants aid in realizing high %yield with Diphenylmethane diisocyanate (MDI) (index 1.587) Color Optimization: Adding MDI gave yellow color. Adding antioxidants, BHT/TNPP, gave white polymer. Amount of solvent: Polyurethane syntheses performed at 20-250 gram made at 10% dilution gave good yields. Solvent Recycling: DMA, methanol used in synthesis, recovery and purification; DMF for dissolution can be recovered by vacuum distillation. Agitator Speed Optimization: optimized to reach full conversion of diisocyanates and diol to form polyurethanes. Scale up: High index BiovexMVP candidate is ready. Acquisition of reactor and spray dryer-solvent recovery unit are needed. Discussion of Results:Optimized reaction produced colorless, optically transparent, tough material in high yield. In order to make Rx lens hydrophobic with no water absorption, aromatic moiety was introduced into the polymer backbone. Key Outcomes: Diisocyanates to hydroxyl at <1.2; crosslinker at 7.2 mol% gave 85% yield. Antioxidants gave white polymer at high yield. Aim 1.5 Major Activity:Create 2nd generation high index and Abbe polymers Data Collected:Made high index monomers and high index polymers. Synthesis of high index monomers and polyurethane: Commercial high index diols/triols were evaluated with MDI (Figure 3, Table 3). Isosorbide dially ether:synthesized (Figure 4) as faint yellow liquid at 70% yield. Isosorbide bisepoxide: synthesized - (i) (Figure 5) to give oligomers, and (ii) (Figure 6) as faint yellow liquid at 75% yield. 2,5-disulfanyl-1,4-dithiane derivative:synthesized (Figure 7) yellow solid at ~30% yield and liquid can be obtained with allyl mercaptan. Dimercapto Isosorbide derivative:synthesized (Figure 8) solid at reasonable yield and liquid can be obtained with allyl mercaptan. Trithiol:synthesized (Figure 9) colorless liquid at reasonable yield. Discussion of Results:High index diols did not yield high molecular weight polyurethanes. Liquid Diallyl, bisepoxy and dithiol derivatives are potential monomers for thiol-ene click thermoset polymers require lens cast molding. Key Outcomes:Successfully made high index monomers and non-yellow polyurethane using commercial high index monomers. Specific Aim 2.1 Major Activity:Optimize the milling process of the polymers Data Collected:Spray drying technique was evaluated to eliminate contamination and sieving issues of polymer. Yamato Scientific's Spray Dryer GB210 equipped with GAS410 Solvent Recovery unit was tested and gave polymer powder (Figure 10). We optimized the process in terms of inlet temperature of drying gas, polymer solution concentration, feed rate of polymer solution into atomizer, inert gas flow pressure, and selecting correct atomizer orifice diameter to yield fine polymer powder. Discussion of Results:Converted polyurethane into fine powders by spray drying. Process was optimized to generate powders in micron size free of contamination and color at 60% yield. Key Outcomes:Spray drying process aided in Biovexfine powders and molding them into bump free lenses. Aim 2.2 Major Activity:Mold high index Biovexinto Rx lenses Data Collected:High index Biovexwas used to mold slabs and Rx lenses by compression molding. Polymers were in large particle form since spray drying method was not used to make fine powders. The Rx lens was made into two steps - slab/disc formation and Rx molding (Figure 11). Discussion of Results:Rx lens produced clear image in lensometer indicating lens had few bumps. Key Outcomes:Successfully molded high index Biovex into Rx lenses using compression molding. Figures and other Tables are attached at: https://drive.google.com/file/d/1KsEZTDcuuY5ys8UwrTmkVq45KkvySxYz/view?usp=sharing

Publications